Tailored oils produced from recombinant oleaginous microorganisms

ABSTRACT

Methods and compositions for the production of oil, fuels, oleochemicals, and other compounds in recombinant microorganisms are provided, including oil-bearing microorganisms and methods of low cost cultivation of such microorganisms. Microalgal cells containing exogenous genes encoding, for example, a lipase, a sucrose transporter, a sucrose invertase, a fructokinase, a polysaccharide-degrading enzyme, a keto acyl-ACP synthase enzyme, a fatty acyl-ACP thioesterase, a fatty acyl-CoA/aldehyde reductase, a fatty acyl-CoA reductase, a fatty aldehyde reductase, a fatty acid hydroxylase, a desaturase enzyme, a fatty aldehyde decarbonylase, and/or an acyl carrier protein are useful in manufacturing transportation fuels such as renewable diesel, biodiesel, and renewable jet fuel, as well as oleochemicals such as functional fluids, surfactants, soaps and lubricants.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/974,983, filed Dec. 18, 2015, which is a continuation of U.S.application Ser. No. 13/365,253, filed Feb. 2, 2012, which claims thebenefit under 35 USC 119(e) of U.S. Provisional Patent Application No.61/438,969, filed Feb. 2, 2011, U.S. Provisional Patent Application No.61/476,691, filed Apr. 18, 2011, U.S. Provisional Patent Application No.61/484,458, filed May 10, 2011, and U.S. Provisional Patent ApplicationNo. 61/548,616, filed Oct. 18, 2011. Each of these applications isincorporated herein by reference in its entirety for all purposes.

REFERENCE TO A SEQUENCE LISTING

This application includes an electronic sequence listing in a file named“473256-Sequence.txt”, created on Dec. 18, 2015 and containing 757,513bytes, which is hereby incorporated by reference in its entirety for allpurposes.

FIELD OF THE INVENTION

The present invention relates to the production of oils, fuels, andoleochemicals made from microorganisms. In particular, the disclosurerelates to oil-bearing microalgae, methods of cultivating them for theproduction of useful compounds, including lipids, fatty acid esters,fatty acids, aldehydes, alcohols, and alkanes, and methods and reagentsfor genetically altering them to improve production efficiency and alterthe type and composition of the oils produced by them.

BACKGROUND OF THE INVENTION

Fossil fuel is a general term for buried combustible geologic depositsof organic materials, formed from decayed plants and animals that havebeen converted to crude oil, coal, natural gas, or heavy oils byexposure to heat and pressure in the earth's crust over hundreds ofmillions of years. Fossil fuels are a finite, non-renewable resource.Increased demand for energy by the global economy has also placedincreasing pressure on the cost of hydrocarbons. Aside from energy, manyindustries, including plastics and chemical manufacturers, rely heavilyon the availability of hydrocarbons as a feedstock for theirmanufacturing processes. Cost-effective alternatives to current sourcesof supply could help mitigate the upward pressure on energy and theseraw material costs.

PCT Pub. No. 2008/151149 describes methods and materials for cultivatingmicroalgae for the production of oil and particularly exemplifies theproduction of diesel fuel from oil produced by the microalgae Chlorellaprotothecoides. There remains a need for improved methods for producingoil for fuel, chemicals, foods and other uses, particularly for methodsthat produce oils with shorter chain length and a higher degree ofsaturation and without pigments, with greater yield and efficiency. Thepresent invention meets this need.

A polyurethane is a compound that comprises a carbamate (urethane)linkage. Typically, a polyurethane is a polymer of organic units. Thepolymer is prepared by the reaction of a first organic unit comprisingan isocyanate moiety (C(O)N—R₁—NC(O)) and a second organic unitcomprising a hydroxyl group (HO—R₂—OH). A polyurethane can berepresented as —[C(O)NH—R₁—NHC(O)—O—R₂—O]_(m)—, wherein the subscript mis a number that denotes the number of monomers contained in thepolymer. R₁ and R₂ can be the same or different, but are typicallydifferent. Polyurethanes are used in many different applicationsincluding both flexible and rigid materials. Polyurethanes are used inshoes, automobiles, airplanes, bushings, gaskets, adhesives, carpeting,spandex fibers, housing for electronics and the like.

SUMMARY OF THE INVENTION

Illustrative embodiments of the present invention provide oleaginouscells that produce altered glycerolipid profiles and products producedfrom the cells. Examples of oleagninous cells include microbial cellshaving a type II lipid biosynthesis pathway. Embodiments also featurenatural oils, which are obtainable using the cells. Embodiments includerecombinant cells expressing exogenous genes encoding proteins such asfatty acyl-ACP thioesterases. The present invention also providesmethods of making lipids and oil-based products, including fuels such asbiodiesel, renewable diesel and jet fuel, food oils and chemicals fromsuch cells.

In a first aspect, the present invention provides a microalgal cellhaving a lipid profile that is at least 3% C8:0. In some cases, thelipid profile is at least 12% C8:0. In some embodiments, the cell is arecombinant cell. In some cases, the recombinant cell comprises anexogenous gene encoding an acyl-ACP thioesterase protein that hashydrolysis activity towards fatty acyl-ACP substrates of chain lengthC8. In some embodiments, the exogenous gene encodes a Cuphea palustrisacyl-ACP thioesterase. In some cases, the cell is a Prototheca cell. Insome cases, the cell is of a microalgal genus or species selected frommicroalgae identified in Table 1.

In a second aspect, the present invention provides a microalgal cellhaving a lipid profile that is at least 4% C10:0. In some cases, thelipid profile is at least 18% C10:0. In some cases, the lipid profile isat least 20% C10:0. In some cases, the lipid content of the microalgalcell further comprises C12:0. In some cases, the ratio of C10:0 to C12:0is at least 3:1. In some cases, the lipid content of the microalgal cellfurther comprises C14:0. In some cases, the ratio of C10:0 to C14:0 isat least 10:1. In some embodiments, the cell is a recombinant cell. Insome cases, the recombinant cell comprises an exogenous gene encoding afatty acyl-ACP thioesterase protein that has hydrolysis activity towardsfatty acyl-ACP substrates of chain length C10. In some embodiments, theexogenous gene encodes a fatty acyl-ACP thioesterase protein from aspecies selected from the group consisting of Cuphea hookeriana andUlmus americana. In some embodiments, the fatty acyl-ACP thioesteraseprotein is from a species selected from the group consisting of Cupheahookeriana and Ulmus americana. In some case, the fatty acyl-ACPthioesterase gene is selected from the group consisting of a fattyacyl-ACP thioesterase gene from Cuphea hookeriana and Ulmus americanathat has hydrolysis activity towards fatty acyl-ACP substrates of chainlength C10.

In some cases, the cell is a Prototheca cell. In some embodiments, thecell is of a microalgal genus or species selected from microalgaeidentified in Table 1.

In a third aspect, the present invention provides a microalgal cellhaving a lipid profile that is at least 13% C12:0. In some cases, thecell is a recombinant cell. In some embodiments, the recombinant cellcomprises an exogenous gene encoding a fatty acyl-ACP thioesteraseprotein that has hydrolysis activity towards fatty acyl-ACP substratesof chain length C12. In some embodiments, the fatty acyl-ACPthioesterase protein is from a species selected from the groupconsisting of Umbellularia californica and Cinnamomum camphora. In somecases, the fatty acyl-ACP thioesterase gene is selected from the groupconsisting of a fatty acyl-ACP thioesterase gene from Umbellulariacalifornica and Cinnamomum camphora that has hydrolysis activity towardsfatty acyl-ACP substrates of chain length C12. In some embodiments, thecell is a Prototheca cell.

In a fourth aspect, the present invention provides a microalgal cellhaving a lipid profile that is at least 10% C14:0. In some cases, thelipid profile is at least 35% C14:0. In some cases, the lipid content ofthe microalgal cell further comprises C12:0. In some cases, the ratio ofC14:0 to C12:0 is at least 3:1. In some cases, the cell is a recombinantcell. In some embodiments, the recombinant cell comprises an exogenousgene encoding a fatty acyl-ACP thioesterase protein that has hydrolysisactivity towards fatty acyl-ACP substrates of chain length C14. In someembodiments, the fatty acyl-ACP thioesterase protein is from a speciesselected from the group consisting of Cinnamomum camphora and Ulmusamericana. In some cases, the fatty acyl-ACP thioesterase gene isselected from the group consisting of a fatty acyl-ACP thioesterase genefrom Cinnamomum camphora and Ulmus americana that has hydrolysisactivity toward fatty acyl-ACP substrates of chain length C14. In somecases, the cell is a Prototheca cell. In some embodiments, the cell isof a microalgal genus or species selected from microalgae identified inTable 1.

In a fifth aspect, the present invention provides a microalgal cellhaving a lipid profile that is at least 15% C16:0. In some cases, thelipid profile is at least 39% C16:0. In some cases, the lipid profile isat least 67% C16:0. In some cases, the cell is a recombinant cell. Insome embodiments, the recombinant cell comprises an exogenous geneencoding a fatty acyl-ACP thioesterase protein that has hydrolysisactivity towards fatty acyl-ACP substrates of chain length C16. In someembodiments, the fatty acyl-ACP thioesterase protein is from a speciesselected from Cuphea hookeriana and Ulmus Americana. In someembodiments, the recombinant cell comprises an exogenous gene encoding afatty acyl-ACP thioesterase protein from a species selected from thegroup consisting of Cuphea hookeriana and Ulmus americana that havehydrolysis activity towards fatty acyl-ACP substrates of chain lengthC16. In some cases, the cell is a Prototheca cell. In some embodiments,the microalgal cell further comprises an endogenous desaturase gene,wherein the endogenous desaturase gene has been mutated to encode adesaturase that is inactive or less active than the non-mutateddesaturase, or wherein, said endogenous desaturase has been deleted fromthe microalgal cell genome.

In a sixth aspect, the present invention provides a microalgal cellhaving a lipid profile that is at least 60% saturated fatty acids. Insome cases the microalgal cell has a lipid profile that is at least 85%saturated fatty acids. In some cases, the cell is a recombinant cell. Insome embodiments, the recombinant cell comprises an exogenous geneencoding a fatty acyl-ACP thioesterase protein that has hydrolysisactivity towards fatty acyl-ACP substrates of chain lengths C10-C16. Insome cases, the cell is a Prototheca cell.

In a seventh aspect, the present invention provides a microalgal cellhaving a lipid profile that is at least 19% C18:0. In some cases, thelipid profile is at least 27% C18:0. In some cases, the cell is arecombinant cell. In some embodiments, the recombinant cell comprises anexogenous gene encoding a fatty acyl-ACP thioesterase protein that hashydrolysis activity towards fatty acyl-ACP substrates of chain lengthC18. In some embodiments, the fatty acyl-ACP thioesterase protein isfrom a species selected from Brassica napus. In some embodiments, therecombinant cell comprises an exogenous gene encoding a fatty acyl-ACPthioesterase protein from Brassica napus that has hydrolysis activitytowards fatty acyl-ACP substrates of chain length C16.

In an eighth aspect, the present invention provides a microalgal cellcomprising an exogenous gene encoding a fatty acyl-ACP thioesteraseprotein from the group consisting of Cuphea hookeriana, Umbellulariacalifornica, Cinnamomun camphora, Cuphea palustris, Cuphea lanceolata,Iris germanica, Myristica fragrans, Garcinia mangostana, Elaeisguiniensis, Brassica napus, Ricinus communis and Ulmus americana.

In an ninth aspect, the present invention provides a microalgal cellcomprising an expression construct wherein the expression constructdown-regulates the expression of an endogenous gene selected from themethods consisting of the endogenous gene has been mutated to encode agene product that is inactive or less active than the non-mutated geneproduct, the endogenous gene has been deleted from the microalgal cellgenome, and through a RNA-induced mechanism. In some cases, the methodis a RNA-induced mechanism, such as RNAi, antisense and/or dsRNA. Insome cases, the endogenous gene is a desaturase gene. In someembodiments, the desaturase gene is a delta 12 fatty acid desaturasegene. In some cases, the cell is a Prototheca cell.

In an tenth aspect, the present invention provides a microalgal cell asdescribed in any of the above aspects, wherein the microalgal cell iscultivated using stachyose, raffinose or melibiose as a carbon source.

In an eleventh aspect, the present invention provides a microalgal cellhaving a lipid profile that is no more than 2% 18:2. In some cases, thepresent invention provides a microalgal cell having a lipid profile thatis no more than 7% 18:2.

In a twelfth aspect, the present invention provides a method of makinglipid. In one embodiment, the method comprises (a) cultivating amicroalgal cell as discussed above until the cell is at least 20% lipidby dry weight; and (b) separating the lipid from water-soluble biomasscomponents.

In a thirteenth aspect, the present invention provides another method ofmaking lipid. In one embodiment, the method comprises (a) cultivating amicroalgal cell containing two different exogenous genes encoding twodifferent acyl-ACP thioesterases, and (b) separating the lipid fromwater-soluble biomass components. In some cases, at least one of theexogenous genes encodes a fatty acyl-ACP thioesterase selected from thegroup consisting of the thioesterases identified in Table 4.

In a fourteenth aspect, the present invention provides a method ofmaking an oil-based product. In one embodiment, the method comprises (a)cultivating a microalgal cell as discussed above until the cell is atleast 10% lipid by dry weight; (b) separating the lipid from themicroalgal cell; (c) subjecting the lipid to at least one chemicalreaction selected from the group consisting of: saponification;metathesis; acid hydrolysis; alkaline hydrolysis; enzymatic hydrolysis;catalytic hydrolysis; hot-compressed water hydrolysis; a catalytichydrolysis reaction wherein the lipid is split into glycerol and fattyacids; an amination reaction to produce fatty nitrogen compounds; anozonolysis reaction to produce mono- and dibasic-acids; a triglyceridesplitting reaction selected from the group consisting of enzymaticsplitting and pressure splitting; a condensation reaction that follows ahydrolysis reaction; a hydroprocessing reaction; a hydroprocessingreaction and a deoxygenation reaction and/or a condensation reactionprior to or simultaneous with the hydroprocessing reaction; a gasremoval reaction; a deoxygenation reaction selected from the groupconsisting of a hydrogenolysis reaction, hydrogenation, a consecutivehydrogenation-hydrogenolysis reaction, a consecutivehydrogenolysis-hydrogenation reaction, and a combinedhydrogenation-hydrogenolysis reaction; a condensation reaction followinga deoxygenation reaction; an esterification reaction; aninterestification reaction; a transesterification reaction; ahydroxylation reaction; and a condensation reaction following ahydroxylation reaction; and (d) optionally isolating a product of thereaction from the other components, whereby an oil-based product isproduced.

In some cases, the oil-based product is selected from soap or a fuelproduct. In some embodiments, the oil-based product is a fuel productselected from the group consisting biodiesel, renewable diesel, and jetfuel. In some cases, the fuel product is biodiesel with one or more ofthe following attributes: (i) 0.025-0.3 mcg/g, preferably 0.05-0.244mcg/g, total carotenoids; (ii) less than 0.005 mcg/g, preferably lessthan 0.003 mcg/g, lycopene; (iii) less than 0.005 mcg/g, preferably lessthan 0.003 mcg/g, beta carotene; (iv) 0.025-0.3 mcg/g, preferably0.045-0.268 mcg/g, chlorophyll A; (v) 35-175 mcg/g, preferably 38.3-164mcg/g, gamma tocopherol; (vi) less than 0.25% brassicasterol,campesterol, stignasterol, or beta-sitosterol; (vii) 225-350 mcg/g,preferably 249.6-325.3 mcg/g, total tocotrienols; (viii) 0.0025-0.05mcg/g, preferably 0.003-0.039 mcg/g, lutein; or (ix) 50-300 mcg/g,preferably 60.8-261.7 mcg/g, tocopherols. In some cases, the fuelproduct is renewable diesel that has a T10-T90 of at least 20° C., 40°C. or 60° C. In some cases, the fuel product is jet fuel that meetsHRJ-5 and/or ASTM specification D1655.

In a fifteenth aspect, the present invention provides a triglyceride oilcomprising (a) a lipid profile of at least 1-5%, preferably at least 3%,C8:0, at least 2.5%, preferably at least 4%, C10:0, at least 10%,preferably at least 13%, C12:0, at least 10% C14:0, and/or at least 60%saturated fatty acids, and (b) one or more of the following attributes:(i) 0.025-0.3 mcg/g, preferably 0.05-0.244 mcg/g, total carotenoids;(ii) less than 0.005 mcg/g, preferably less than 0.003 mcg/g, lycopene;(iii) less than 0.005 mcg/g, preferably less than 0.003 mcg/g, betacarotene; (iv) 0.025-0.3 mcg/g, preferably 0.045-0.268 mcg/g,chlorophyll A; (v) 35-175 mcg/g, preferably 38.3-164 mcg/g, gammatocopherol; (vi) less than 0.25% brassicasterol, campesterol,stignasterol, or beta-sitosterol; (vii) 225-350 mcg/g, preferably249.6-325.3 mcg/g, total tocotrienols; (viii) 0.0025-0.05 mcg/g,preferably 0.003-0.039 mcg/g, lutein; or (ix) 50-300 mcg/g, preferably60.8-261.7 mcg/g, tocopherols.

In a sixteenth aspect, the present invention provides a triglyceride oilisolated from microalgae that has a C8:C10 fatty acid ratio of at least5:1. In some embodiments, the triglyceride oil is isolated frommicroalgal cell (e.g., of the genus Prototheca), wherein the microalgalcell comprises an exogenous gene. In a related aspect, the presentinvention provides a triglyceride oil isolated from microalgae with atleast 60% saturated fatty acids.

In another related aspect, the present invention provides a triglycerideoil isolated from microalgae having a lipid profile that has a C16:14fatty acid ratio of about 2:1. In another related aspect, the presentinvention provides a triglyceride oil produced by a microalgal cell,wherein the microalgal cell comprises an exogenous gene. In some cases,the microalgae is of the genus Prototheca.

In another related aspect, the present invention provides a triglycerideoil isolated from microalgae having a lipid profile that has a C12:14fatty acid ratio of about 3:1. In another related aspect, the presentinvention provides a triglyceride oil produced by a microalgal cell,wherein the microalgal cell comprises an exogenous gene. In some cases,the microalgae is of the genus Prototheca.

In a seventeenth aspect, the present invention provides a triglycerideoil comprising (a) a lipid profile of less than 1%<C12; between 1%-10%,preferably 2%-7%, C14:0; between 20%-35%, preferably 23%-30%, C16:0;between 5%-20%, preferably 7%-15%, C18:0; between 35%-60%, preferably40%-55%, C18:1; and between 1%-20%, preferably 2%-15%, C18:2 fattyacids; and (b) one or more of the following attributes: (i) 0.025-0.3mcg/g, preferably 0.05-0.244 mcg/g, total carotenoids; (ii) less than0.005 mcg/g, preferably less than 0.003 mcg/g, lycopene; (iii) less than0.005 mcg/g, preferably less than 0.003 mcg/g, beta carotene; (iv)0.025-0.3 mcg/g, preferably 0.045-0.268 mcg/g, chlorophyll A; (v) 35-175mcg/g, preferably 38.3-164 mcg/g, gamma tocopherol; (vi) less than 0.25%brassicasterol, campesterol, stignasterol, or beta-sitosterol; (vii)225-350 mcg/g, preferably 249.6-325.3 mcg/g, total tocotrienols; (viii)0.0025-0.05 mcg/g, preferably 0.003-0.039 mcg/g, lutein; or (ix) 50-300mcg/g, preferably 60.8-261.7 mcg/g, tocopherols.

In some cases, the triglyceride oil is isolated from a microbecomprising one or more exogenous gene. In some embodiments, the one ormore exogenous gene encodes a fatty acyl-ACP thioesterase. In somecases, the fatty acyl-ACP thioesterase has hydrolysis activity towardsfatty acyl-ACP substrates of chain length C14. In some embodiments, themicrobe further comprising expression construct wherein the expressionconstruct down-regulates the expression of an endogenous gene selectedfrom the methods consisting of the endogenous gene has been mutated toencode a gene product that is inactive or less active than thenon-mutated gene product, the endogenous gene has been deleted from themicroalgal cell genome, and through a RNA-induced mechanism. In someembodiments, the endogenous gene encodes a desaturase. In some cases,the desaturase is a stearoyl-acyl carrier protein desaturase (SAD) or afatty acid desaturase (FAD).

In an eighteenth aspect, the present invention provides a method ofproducing a triglyceride oil comprising a lipid profile of less than1%<C12; between 2%-7% C14:0; between 23%-30% C16:0; between 7%-15%C18:0; between 40-55% C18:1; and between 2-15% C18:2 fatty acids,wherein the triglyceride oil is isolated from a microbe comprising oneor more exogenous gene. In some cases, the triglyceride oil comprises alipid profile of 3-5% C14:0; 25-27% C16:0; 10-15% C18:0; and 40-45%C18:1. In some embodiments, the one or more exogenous gene encodes afatty acyl-ACP thioesterase. In some cases, the fatty acyl-ACPthioesterase has hydrolysis activity towards fatty acyl-ACP substratesof chain length C14.

In a nineteenth aspect, the present invention provides a microbial cellthat produces ricinoleic acid. In some cases, the microbial cell is amicroalgal cell. In some cases, the microbial cell and the microalgalcell comprises an exogenous gene that encodes a fatty acid hydroxylase.In some embodiments, the fatty acid hydroxylase is an oleate12-hydroxylase. In some cases, the fatty acid hydroxylase is fromRicinus communis. In some cases, the microbial cell is of the genusPrototheca, such as, for example Prototheca moriformis.

In a twentieth aspect, the present invention provides a microalgal cellcomprising an exogenous gene that encodes an alpha-galactosidase. Insome cases, the microalgal cell comprising an exogenous gene thatencodes an alpha-galactosidase wherein the alpha-galactosidase issecreted. In some embodiments, the exogenous gene that encodes analpha-galactosidase is from a genus selected from the group consistingof Saccharomyces, Aspergillus and Cyamopsis.

In a twentyfirst aspect, the present invention provides a method ofproducing a lipid composition comprising the steps of: (a) cultivating amicroalgal cell under heterotrophic conditions in the presence of afixed carbon source, wherein the microalgal cell comprises an exogenousgene encoding an alpha-galactosidase and the fixed carbon source isselected from the group consisting of raffinose, stachyose andmelibiose; (b) separating the lipid from the non-lipid components;thereby producing a lipid composition. In some cases, the microalgalcell is of the genus Prototheca.

In a twentysecond aspect, the present invention provides a microalgalcell comprising an exogenous gene that encodes a THIC enzyme. In somecases, the THIC enzyme is from a genus selected from the groupconsisting of Coccomyxa, Arabidopsis, and Synechocystis.

In another aspect, the present invention provides a method ofcultivating a microalgal cell in the absence of thiamine comprisingexpressing an exogenous gene that encodes a THIC enzyme. In some cases,the THIC enzyme is from a genus selected from the group consisting ofCoccomyxa, Arabidopsis, and Synechocystis.

In other aspects, the present invention provides a microalgal cell asdescribed herein, wherein said microalgal cell further comprises anotherexogenous gene selected from the group consisting of a sucroseinvertase, an alpha-galactosidase, and a THIC enzyme.

Another aspect of this invention provides a hydroxylated oil isolatedfrom a microbial cell. In one aspect, the hydroxylated oil is isolatedfrom a microbial cell, wherein the microbial cell is a microalgal cell(e.g., of the genus Prototheca). In a further aspect, the hydroxylatedoil is isolated from a Prototheca moriformis cell. In one embodiment,the hydroxylated oil is a hydroxylated triglyceride. The hydroxylatedtriglyceride may be chemically similar or identical to castor oil.

A further aspect of the invention is a hydroxylated fatty acid. Oneembodiment of the hydroxylated fatty acid is ricinoleic acid.

In yet another aspect, the microbial hydroxylated oil or hydroxylatedfatty acid is further hydroxylated. When ricinoleic acid ishydroxylated, a fatty acid containing two hydroxyl groups is provided.

Yet another aspect of the invention provides a composition prepared byreacting a hydroxylated oil and/or a hydroxylated fatty acid with acompound that contains an isocyanate moiety to form a polyurethane.

Another aspect of the invention provides a microalgal cell having alipid profile that is at least 20% C18:2. In some cases, the microalgalcell has a lipid profile that is at least 30% C18:2. In some cases, themicroalgal cell has a lipid profile that is at least 40% C18:2. In somecases, the microalgal cell has a lipid profile that is at least 50%C18:2.

Another aspect of the invention provides a method of making a lipid,comprising: (a) cultivating a microalgal cell in a culture medium andmonitoring the sugar concentration; (b) when the sugar concentration ofthe culture medium reaches less than about 1 gram per liter, adding afirst sugar solution to the culture medium at a continuous rate ofbetween about 2 grams per hour per liter to about 10 grams per hour perliter for about 2 to about 24 hours; (c) adding a second sugar solutionto the culture medium to maintain the sugar concentration of the culturemedium at about 15 to about 20 grams per liter; and (d) isolating thelipid from the microalgal biomass. In some cases, the first sugarsolution is added to the culture medium at a rate of about 4 grams ofsucrose per hour per liter to about 6 grams of sucrose per hour perliter. In some cases, the first sugar solution is added to the culturemedium at a rate of about 5.25 grams of sucrose per hour per liter. Insome cases, the sugar is sucrose or glucose.

Another aspect of the invention provides a microalgal cell having alipid profile that is at least 10% C18:3. In some cases, the microalgalcell has a lipid profile that is at least 20% C18:3. In some cases, themicroalgal cell has a lipid profile that is at least 30% C18:3. In somecases, the microalgal cell has a lipid profile is at least 40% C18:3. Insome cases, the microalgal cell has a lipid profile is at least 50%C18:3.

Another aspect of the invention provides a microorganism that produces atriglyceride comprising linoleic acid or linolenic acid, wherein themicroorganism comprises a recombinant nucleic acid encoding aβ-ketoacyl-ACP synthase II (KAS II) enzyme. In some cases, themicroorganism further comprises a recombinant nucleic acid encoding astearoyl ACP desaturase (SAD) enzyme. In some cases, the microorganismfurther comprises a recombinant nucleic acid encoding an oleate-specificthioesterase enzyme. In some cases, the microorganism further comprisesa recombinant nucleic acid encoding a fatty acid desaturase (FAD)enzyme. In some cases, the microorganism further comprises a recombinantnucleic acid encoding a glycerolipid desaturase.

In the engineered microorganisms discussed above, the KAS II enzyme cancomprise an amino acid sequence selected from the group consisting ofSEQ ID NO: 175, SEQ ID NO: 176, SEQ ID NO: 177, SEQ ID NO: 178 and SEQID NO: 179. In some cases, the SAD enzyme can comprise an amino acidsequence selected from the group consisting of SEQ ID NO: 172, SEQ IDNO: 196, SEQ ID NO: 197, SEQ ID NO: 198, SEQ ID NO: 199, SEQ ID NO: 200,and SEQ ID NO: 201. In some cases, the oleate-specific thioesteraseenzyme can comprise an amino acid sequence selected from the groupconsisting of SEQ ID NO: 195, SEQ ID NO: 202, SEQ ID NO: 203, SEQ ID NO:204, SEQ ID NO: 205, and SEQ ID NO: 206. In some cases, the FAD enzymecan comprise an amino acid sequence seleted from the group consisting ofSEQ ID NO: 181, SEQ ID NO: 182. SEQ ID NO: 183, SEQ ID NO: 184 and SEQID NO: 185. In some cases, the FAD enzyme is a Δ12 FAD enzyme comprisingan amino acid sequence selected from the group consisting of SEQ ID NO:207, SEQ ID NO: 208, SEQ ID NO: 209, SEQ ID NO: 210, SEQ ID NO: 211, andSEQ ID NO: 212. In some cases, the FAD enzyme is a Δ15 FAD enzymecomprising an amino acid sequence selected from the group consisting ofSEQ ID NO: 213, SEQ ID NO: 214, SEQ ID NO: 215, SEQ ID NO: 216, SEQ IDNO: 217, SEQ ID NO: 218, SEQ ID NO: 219, SEQ ID NO: 220, and SEQ ID NO:221. In some cases, the glycerolipid desaturase is a ω-6 fatty aciddesaturase, a ω-3 fatty acid desaturase, or a ω-6 oleate desaturase.

Any one of the engineered microorgansims discussed above can furthercomprise a recombinant nucleic acid encoding a sucrose utilizationpathway enzyme. In some cases, the sucrose utilization pathway enzyme isa sucrose invertase.

In any one of the engineered microorganisms discussed above, themicroorganism can be further engineered to increase the proportion oflinoleic acid or linolenic acid relative to other fatty acids.

In any one of the engineered microorganisms discussed above, themicroorganism can be further engineered to overexpress a thioesterasespecific for or preferential to C18 substrates.

In any one of the engineered microorganisms discussed above, themicroorganism can be further engineered to decrease expression of athioesterase specific for or preferential to a C8-C16 substrate.

In any one of the engineered microorganisms discussed above, themicroorganism can be a microalgal cell. In some cases, the microalgalcell is of the genus Prototheca. In some cases, the microalgal cell is aPrototheca moriformis cell.

Another aspect of the invention provides an oil produced by any one ofthe engineered microorganisms discussed above.

Another aspect of the invention provides methods of producing theengineered microorganisms discussed above by introducing into themicroorganisms one or more of the recombinant nucleic acids to producetriglycerides comprising linoleic acid or linolenic acid.

Another aspect of the invention provides a method for producing anatural oil comprising triacylglycerides, or a product produced from thenatural oil, in which the method comprises (i) cultivating a cell of arecombinant microorganism, the cell comprising recombinant nucleic acidsoperable to (a) decrease or eliminate the expression of an enzymeencoded by one or more genes that encode a β-ketoacyl-ACP synthase I,β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, fatty aciddesaturase, or acyl-ACP thioesterase, and optionally wherein the cellcomprises recombinant nucleic acids operable to decrease or eliminatethe expression of two copies of a gene encoding a β-ketoacyl-ACPsynthase I, β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, orfatty acid desaturase, or acyl-ACP thioesterase; or (b) express aproduct of an exogenous gene encoding an active β-ketoacyl-ACP synthaseI, β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, or fatty aciddesaturase, or acyl-ACP thioesterase; or (c) decrease or eliminate theexpression of an enzyme encoded by one or more genes that encode aβ-ketoacyl-ACP synthase I or β-ketoacyl-ACP synthase II, and express aproduct of an exogenous gene encoding an active stearoyl ACP desaturase,fatty acid desaturase, or acyl-ACP thioesterase; or (d) decrease oreliminate the expression of an enzyme encoded by one or more genes thatencode a stearoyl ACP desaturase or fatty acid desaturase, and express aproduct of an exogenous gene encoding an active β-ketoacyl-ACP synthaseI, β-ketoacyl-ACP synthase II, or acyl-ACP thioesterase; and (ii)recovering the natural oil from the cell, and optionally furtherprocessing the natural oil to produce a food, fuel, or chemical product,wherein the natural oil has an altered fatty acid profile due to therecombinant nucleic acids.

In some cases, the microorganism synthesizes fatty acids through a typeII fatty acid biosynthesis pathway. In some cases, the microorganism isa microalga. In some cases, the microalga is an obligate heterotroph. Insome cases, the microalga is a species of Prototheca or Chlorella. Insome cases, the microalga is Prototheca wickerhamii, Protothecastagnora, Prototheca portoricensis, Prototheca moriformis, or Protothecazopfii. In some cases, the microalga is Chlorella kessleri, Chlorellaluteoviridis Chlorella protothecoides, or Chlorella vulgaris. In somecases, the cell is a recombinant cell expressing an active sucroseinvertase. In some cases, the cultivating is heterotrophic. In somecases, the fatty acid desaturase is one or more of a ω-6 fatty aciddesaturase, a ω-3 fatty acid desaturase, or a ω-6 oleate desaturase, ora delta 12 fatty acid desaturase. In some cases, the cell is cultivatedso as to comprise between at least 50%, at least 60%, at least 70%, or50 and 90% triglyceride by dry cell weight. In some cases, the oilcomprises less than 500, 50, or 5 ppm of colored molecules. In somecases, the recombinant nucleic acids are stably integrated. In somecases, the recombinant nucleic acids are stably integrated into thechromosome of the microorganism. In some cases, the cell furthercomprises at least one selectable marker.

In some cases, the cell comprises recombinant nucleic acids operable todecrease or eliminate the expression of an enzyme through expression ofantisense, RNAi, or dsRNA targeting the transcript of a gene encodingfor the enzyme. In some cases, the decrease or elimination of theexpression of an enzyme encoded by one or more genes that encode aβ-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthase II, stearoyl ACPdesaturase, or fatty acid desaturase is due to the interruption orreplacement of the one or more genes with one or more genes encoding anactive β-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthase II, stearoylACP desaturase, or fatty acid desaturase, or acyl-ACP thioesterase. Insome cases, the recombinant cell further comprises an exogenous geneencoding an oleate 12-hydroxylase, so as to synthesize ricinoleic acid.In some cases, the recombinant cell comprises nucleic acids operable todecrease or eliminate the expression of a β-ketoacyl-ACP synthase IIencoded by a KASII gene, and to express a product of an exogenous geneencoding an acyl-ACP thioesterase. In some cases, the cell produces anoil with a fatty acid profile characterized by having at least 40, 50,60, 70, or 80% C16 fatty acids. In some cases, the cell produces an oilwith a fatty acid profile characterized by having at least 50-75% C16:0.In some cases, the cell produces an oil with a fatty acid profilefurther characterized by having at least 20-40% C18:1. In some cases,the exogenous gene encoding an acyl-ACP thioesterase produces an activeacyl-ACP thioesterase having greater activity in hydrolysis of C8-C16fatty acyl chains than a native acyl-ACP-thioestearase of the cell. Insome cases, the exogenous gene encoding an acyl-ACP thioesteraseinterrupts the KASII gene. In some cases, the recombinant cell comprisesnucleic acids operable to decrease or eliminate the expression of anenzyme encoded by one or more genes that encode a β-ketoacyl-ACPsynthase I.

In some cases, the oil produced has a fatty acid profile characterizedby a shorter mean fatty acid chain length as a result of the recombinantnucleic acids. In some cases, the recombinant cell comprises nucleicacids operable to decrease or eliminate the expression of a fatty aciddestaurase encoded by at least one FAD gene and express a product of astearoyl-ACP desaturase exogenous gene encoding an active stearoyl ACPdesaturase. In some cases, nucleic acids are operable to decrease oreliminate the expression of a fatty acid destaurase encoded by multiplecopies of a fatty acid desaturase gene. In some cases, the Stearoyl-ACPdesaturase exogenous gene is recombined into a locus within the codingregion of the fatty acid desaturase gene. In some cases, the oilproduced has a fatty acid profile having elevated oleic acid. In somecases, the oleic acid comprises at least 50, 60, 70, 80, or 90% of thefatty acids. In some cases, the recombinant cell comprises nucleic acidsoperable to express a product of a β-ketoacyl-ACP synthase II exogenousgene encoding an active β-ketoacyl-ACP synthase II. In some cases, theoil produced is characterized by a fatty acid profile elevated in C18:1fatty acids and reduced in C16 fatty acids as a result of therecombinant nucleic acids. In some cases, the recombinant cell comprisesnucleic acids operable to decrease or eliminate the expression of anenzyme encoded by one or more genes that encode a stearoyl ACPdesaturase by RNA interference. In some cases, the oil produced has afatty acid profile characterized by an increase in C18:0 fatty acids. Insome cases, the oil produced is characterized by a fatty acid profilehaving at least 50, 60, 70, 80, or 90% C18:0. In some cases, the oilproduced is characterized by a fatty acid profile having at least 50-75%C18:0. In some cases, the oil produced is further characterized by afatty acid profile having at least 20-40% C18:1. In some cases, the cellcomprises recombinant nucleic acids operable to decrease or eliminatethe expression of two copies of a gene encoding a β-ketoacyl-ACPsynthase I, β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, orfatty acid desaturase. In some cases, the nucleic acids are operable toexpress a product of a fatty acid desaturase exogenous gene encoding anactive a ω-3 fatty acid desaturase and/or a ω-6 oleate desaturase. Insome cases, the oil produced has a fatty acid profile characterized byan elevated level of linoleic acid, linolenic acid, or both. In somecases, the fatty acid profile of the oil is characterized by having atleast 10, 20, 30, 40, or 50% linoleic acid, linolenic acid, or both. Insome cases, the further processing of the oil comprises one or more ofrefining, bleaching, deodorizing, metathesis, transesterification,hydrogenation, hydrolysis, hydrogenation, deoxygenation, hydrocracking,isomerization, hydrolxylation, interesterification, amidation,sulfonation, and sulfurization. In some cases, the oil is processed tocreate a food oil, fatty acids, a fatty alcohol, a lubricant, a soap, afatty acid ester, a fatty acid ethoxylate, a fatty amine, an akylchloride, a fatty alcohol ethoxylate, a fatty alcohol sulfate, a fattyacid alkanolamide, a sulfonated oil, a sulfurized oil, diesel fuel, jetfuel, gasoline, fuel blendstock, fuel additive, lubricant additive, orcoating.

Another aspect of the invention provides natural oil obtainable by themethods discussed above.

Another aspect of the invention provides a product made from the naturaloil discussed above. In some cases, the product comprises a food oil,fatty acids, a fatty alcohol, a lubricant, a soap, a fatty acid ester, afatty acid ethoxylate, a fatty amine, an akyl chloride, a fatty alcoholethoxylate, a fatty alcohol sulfate, a fatty acid alkanolamide, asulfonated oil, a sulfurized oil, diesel fuel, jet fuel, gasoline, fuelblendstock, fuel additive, chemical additive, or coating.

Another aspect of the invention provides a recombinant cell comprisingrecombinant nucleic acids operable to (a) decrease or eliminate theexpression of an enzyme encoded by one or more genes that encode aβ-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthase II, stearoyl ACPdesaturase, fatty acid desaturase, or acyl-ACP thioesterase, andoptionally wherein the cell comprises recombinant nucleic acids operableto decrease or eliminate the expression of two copies of a gene encodinga β-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthase II, stearoyl ACPdesaturase, or fatty acid desaturase, or acyl-ACP thioesterase; or (b)express a product of an exogenous gene encoding an active β-ketoacyl-ACPsynthase I, β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, orfatty acid desaturase, or acyl-ACP thioesterase; or (c) decrease oreliminate the expression of an enzyme encoded by one or more genes thatencode a β-ketoacyl-ACP synthase I or β-ketoacyl-ACP synthase II, andexpress a product of an exogenous gene encoding an active stearoyl ACPdesaturase, fatty acid desaturase, or acyl-ACP thioesterase; or (d)decrease or eliminate the expression of an enzyme encoded by one or moregenes that encode a stearoyl ACP desaturase or fatty acid desaturase,and express a product of an exogenous gene encoding an activeβ-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthase II, or acyl-ACPthioesterase.

In some cases, the microorganism synthesizes fatty acids through a typeII fatty acid biosynthesis pathway. In some cases, the microorganism isa microalga. In some cases, the microalga is an obligate heterotroph. Insome cases, the microalga is a species of Prototheca or Chlorella. Insome cases, the microalga is Prototheca wickerhamii, Protothecastagnora, Prototheca portoricensis, Prototheca moriformis, or Protothecazopfii. In some cases, the microalga is Chlorella kessleri, Chlorellaluteoviridis Chlorella protothecoides, or Chlorella vulgaris. In somecases, the cell is a recombinant cell expressing an active sucroseinvertase. In some cases, the cell is capable of heterotrophic growth.In some cases, the fatty acid desaturase is one or more of a ω-6 fattyacid desaturase, a ω-3 fatty acid desaturase, or a ω-6 oleatedesaturase, or a delta 12 fatty acid desaturase. In some cases, the cellis capable of being cultivated so as to comprise between at least 50%,at least 60%, at least 70%, or 50 and 90% triglyceride by dry cellweight. In some cases, the recombinant nucleic acids are stablyintegrated. In some cases, the recombinant nucleic acids are stablyintegrated into the chromosome of the microorganism. In some cases, thecell further comprises at least one selectable marker. In some cases,the cell comprises recombinant nucleic acids operable to decrease oreliminate the expression of an enzyme through expression of antisense,RNAi, or dsRNA targeting the transcript of a gene encoding for theenzyme. In some cases, the decrease or elimination of the expression ofan enzyme encoded by one or more genes that encode a β-ketoacyl-ACPsynthase I, β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, orfatty acid desaturase is due to the interruption or replacement of theone or more genes with one or more genes encoding an activeβ-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthase II, stearoyl ACPdesaturase, or fatty acid desaturase, or acyl-ACP thioesterase.

In some cases, the recombinant cell further comprises an exogenous geneencoding an oleate 12-hydroxylase, so as to synthesize ricinoleic acid.In some cases, the recombinant cell comprises nucleic acids operable todecrease or eliminate the expression of a β-ketoacyl-ACP synthase IIencoded by a KASII gene, and to express a product of an exogenous geneencoding an acyl-ACP thioesterase. In some cases, the cell produces anoil with a fatty acid profile characterized by having at least 40, 50,60, 70, or 80% C16 fatty acids. In some cases, the cell produces an oilwith a fatty acid profile characterized by having at least 50-75% C16:0.In some cases, the cell produces an oil with a fatty acid profilefurther characterized by having at least 20-40% C18:1. In some cases,the exogenous gene encoding an acyl-ACP thioesterase produces an activeacyl-ACP thioesterase having greater activity in hydrolysis of C8-C16fatty acyl chains than a native acyl-ACP-thioestearase of the cell. Insome cases, the exogenous gene encoding an acyl-ACP thioesteraseinterrupts the KASII gene. In some cases, the recombinant cell comprisesnucleic acids operable to decrease or eliminate the expression of anenzyme encoded by one or more genes that encode a β-ketoacyl-ACPsynthase I. In some cases, the oil produced has a fatty acid profilecharacterized by a shorter mean fatty acid chain length as a result ofthe recombinant nucleic acids. In some cases, the recombinant cellcomprises nucleic acids operable to decrease or eliminate the expressionof a fatty acid destaurase encoded by at least one FAD gene and expressa product of a stearoyl-ACP desaturase exogenous gene encoding an activestearoyl ACP desaturase. In some cases, the nucleic acids are operableto decrease or eliminate the expression of a fatty acid destauraseencoded by multiple copies of a fatty acid desaturase gene. In somecases, the Stearoyl-ACP desaturase exogenous gene is recombined into alocus within the coding region of the fatty acid desaturase gene.

In some cases, the oil produced has a fatty acid profile having elevatedoleic acid. In some cases, the oleic acid comprises at least 50, 60, 70,80, or 90% of the fatty acids. In some cases, the recombinant cellcomprises nucleic acids operable to express a product of aβ-ketoacyl-ACP synthase II exogenous gene encoding an activeβ-ketoacyl-ACP synthase II. In some cases, the oil produced ischaracterized by a fatty acid profile elevated in C18:1 fatty acids andreduced in C16 fatty acids as a result of the recombinant nucleic acids.In some cases, the recombinant cell comprises nucleic acids operable todecrease or eliminate the expression of an enzyme encoded by one or moregenes that encode a stearoyl ACP desaturase by RNA interference. In somecases, the oil produced has a fatty acid profile characterized by anincrease in C18:0 fatty acids. In some cases, the oil produced ischaracterized by a fatty acid profile having at least 50, 60, 70, 80, or90% C18:0. In some cases, the oil produced is characterized by a fattyacid profile having at least 50-75% C18:0. In some cases, the oilproduced is further characterized by a fatty acid profile having atleast 20-40% C18:1. In some cases, the cell comprises recombinantnucleic acids operable to decrease or eliminate the expression of twocopies of a gene encoding a β-ketoacyl-ACP synthase I, β-ketoacyl-ACPsynthase II, stearoyl ACP desaturase, or fatty acid desaturase. In somecases, the nucleic acids are operable to express a product of a fattyacid desaturase exogenous gene encoding an active a ω-3 fatty aciddesaturase and/or a ω-6 oleate desaturase. In some cases, the oilproduced has a fatty acid profile characterized by an elevated level oflinoleic acid, linolenic acid, or both. In some cases, the fatty acidprofile of the oil is characterized by having at least 10, 20, 30, 40,or 50% linoleic acid, linolenic acid, or both.

Another aspect of the invention provides a natural oil or oil-containingproduct produced from the cells described above.

Another aspect of the invention provides a method for producing anatural oil comprising triacylglycerides that comprise ricinoleic acid,or a product produced from the natural oil, the method comprisingcultivating a cell of a recombinant microorganism, the cell comprisingrecombinant nucleic acids operable to express a product of an exogenousgene encoding an active oleate 12-hydroxylase, so as to synthesize thericinoleic acid.

In some cases, the microorganism has a type II fatty acid biosynthesispathway. In some cases, the microorganism is a microalga. In some cases,the microalga is an obligate heterotroph. In some cases, the microalgais a species of Prototheca. In some cases, the microalga is Protothecawickerhamii, Prototheca stagnora, Prototheca portoricensis, Protothecamoriformis, or Prototheca zopfii. In some cases, the microalga isChlorella kessleri, Chlorella luteoviridis Chlorella protothecoides, orChlorella vulgaris. In some cases, the cell is a recombinant cellexpressing an active sucrose invertase. In some cases, the cultivatingis heterotrophic. In some cases, the cell produces at least 40, 50, 60,70, 80, or 90% oleic acid absent the recombinant nucleic acids operableto express a product of an exogenous gene encoding an active oleate12-hydroxylase. In some cases, the cell further comprises recombinantnucleic acids operable to enhance oleic acid production so as to elevatethe substrate levels for the oleate 12-hydroxylase. In some cases, thecell comprises recombinant nucleic acids operable to (a) express aproduct of an exogenous gene encoding an active stearoyl ACP desaturaseand decrease or eliminate the expression of an enzyme encoded by one ormore genes that encode a fatty acid desaturase; or (b) express a productof an exogenous gene encoding an active β-ketoacyl-ACP synthase I andexpress a product of an exogenous gene encoding an active acyl-ACPthioesterase.

Another aspect of the invention provides a product produced according toany of the methods discussed above.

Another aspect of the invention provides a microorganism cell comprisingrecombinant nucleic acids operable to express a product of an exogenousgene encoding an active oleate 12-hydroxylase, so as to synthesizericinoleic acid.

In some cases, the microorganism has a type II fatty acid biosynthesispathway. In some cases, the microorganism is a microalga. In some cases,the microalga is an obligate heterotroph. In some cases, the microalgais a species of Prototheca. In some cases, the microalga is Protothecawickerhamii, Prototheca stagnora, Prototheca portoricensis, Protothecamoriformis, or Prototheca zopfii. In some cases, the microalga isChlorella kessleri, Chlorella luteoviridis Chlorella protothecoides, orChlorella vulgaris. In some cases, the cell is a recombinant cellexpressing an active sucrose invertase. In some cases, the cell iscapable of heterotrophic growth. In some cases, the cell produces atleast 40, 50, 60, 70, 80, or 90% oleic acid absent the recombinantnucleic acids operable to express a product of an exogenous geneencoding an active oleate 12-hydroxylase. In some cases, the cellfurther comprises recombinant nucleic acids operable to enhance oleicacid production so as to elevate the substrate levels for the oleate12-hydroxylase. In some cases, the cell comprises recombinant nucleicacids operable to (a) express a product of an exogenous gene encoding anactive stearoyl ACP desaturase and decrease or eliminate the expressionof an enzyme encoded by one or more genes that encode a fatty aciddesaturase; or (b) express a product of an exogenous gene encoding anactive β-ketoacyl-ACP synthase I and express a product of an exogenousgene encoding an active acyl-ACP thioesterase.

Another aspect of the present invention provides a food comprising anoil as discussed above.

These and other aspects and embodiments of the invention are describedin the accompanying drawing, a brief description of which immediatelyfollows, the detailed description of the invention below, and areexemplified in the examples below. Any or all of the features discussedabove and throughout the application can be combined in variousembodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a chromatogram of renewable diesel produced from Protothecatriglyceride oil.

FIG. 2 shows GC retention times of a representative positive transgenicclone compared to the ricinoleic acid standard and a wildtype control.

FIG. 3 shows PstI restriction maps of Prototheca moriformis FADc alleleswith and without a targeted gene disruption, as described in Example 18.

FIG. 4 shows the results of the Southern blot described in Example 18.

DETAILED DESCRIPTION OF THE INVENTION

Illustrative embodiments of the present invention feature oleaginouscells that produce altered glycerolipid profiles and products producedfrom the cells. Examples of oleagninous cells include microbial cellshaving a type II lipid biosynthesis pathway. Embodiments includerecombinant cells expressing one or more exogenous genes encodingproteins such as fatty acyl-ACP thioesterases, fatty acid desaturases,keto-acyl synthases and optionally having one or more knockdowns ofendogenous genes encoding proteins with similar activities. As a result,some embodiments feature natural oils never before obtainable. Thepresent invention also provides methods of making lipids and oil-basedproducts, including fuels such as biodiesel, renewable diesel and jetfuel, food oils and chemicals from such cells.

The oils produced according to embodiments of the present invention canbe used in the transportation fuel, oleochemical, and/or food andcosmetic industries, among other applications. For example,transesterification of lipids can yield long-chain fatty acid estersuseful as biodiesel. Other enzymatic and chemical processes can betailored to yield fatty acids, aldehydes, alcohols, alkanes, andalkenes. In some applications, renewable diesel, jet fuel, or otherhydrocarbon compounds are produced. The present invention also providesmethods of cultivating microalgae for increased productivity andincreased lipid yield, and/or for more cost-effective production of thecompositions described herein.

An embodiment of the invention provides a method for producing a naturaloil comprising triacylglycerides, or for producing a product producedfrom the natural oil. The natural oil can be a non-plant or non-seedoil. The method comprises cultivating a cell of a recombinantmicroorganism to produce a tailored oil; i.e., one with an altered fattyacid profile due to the presence of the recombinant nucleic acids in thecell. The natural oil can then be further processed to produce a food,fuel, or chemical product. The recombinant nucleic acids in the cell areoperable to (a) decrease or eliminate the expression of an enzymeencoded by one or more genes that encode a β-ketoacyl-ACP synthase I,β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, fatty aciddesaturase, or acyl-ACP thioesterase. Optionally the cell comprisesrecombinant nucleic acids operable to decrease or eliminate theexpression of two copies of a gene (e.g., two alleles in a diploidorganism) encoding a β-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthaseII, stearoyl ACP desaturase, or fatty acid desaturase, or acyl-ACPthioesterase; or (b) express a product of a exogenous gene encoding anactive β-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthase II, stearoylACP desaturase, or fatty acid desaturase, or acyl-ACP thioesterase; or(c) decrease or eliminate the expression of an enzyme encoded by one ormore genes that encode a β-ketoacyl-ACP synthase I or β-ketoacyl-ACPsynthase II, and express a product of a exogenous gene encoding anactive stearoyl ACP desaturase, fatty acid desaturase, or acyl-ACPthioesterase; or (d) decrease or eliminate the expression of an enzymeencoded by one or more genes that encode a stearoyl ACP desaturase orfatty acid desaturase, and express a product of an exogenous geneencoding an active β-ketoacyl-ACP synthase I, β-ketoacyl-ACP synthaseII, or acyl-ACP thioesterase.

Where a recombinant nucleic acid encoding one or more fatty aciddesaturases is present in the cell, the nucleic acid may encode for oneor more of a ω-6 fatty acid desaturase, a ω-3 fatty acid desaturase, ora ω-6 oleate desaturase, or a delta 12 fatty acid desaturase.

Where the cell comprises recombinant nucleic acids operable to decreaseor eliminate the expression of an enzyme, this may occur throughexpression of antisense, RNAi, or dsRNA targeting the transcript of agene encoding for the enzyme, or by other suitable means, including adirected mutation, complete deletion, or partial deletion. Thus, thedecrease or alimentation of the expression of an enzyme encoded by oneor more genes that encode a β-ketoacyl-ACP synthase I, β-ketoacyl-ACPsynthase II, stearoyl ACP desaturase, or fatty acid desaturase can bedue to the interruption or replacement of the one or more genes with oneor more genes encoding an active β-ketoacyl-ACP synthase I,β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, or fatty aciddesaturase, or acyl-ACP thioesterase.

Preferably, the recombinant nucleic acids are stably integrated into thecell; e.g., into the cells chromosome, or an episome. The selection ofcells with stably integrated nucleic acids may be aided using aselectable marker such as sucrose invertase, an antibiotic resistancegene, or thiamine auxotrophy complementation, as described herein.

Preferably, the microorganism can be one that synthesizes fatty acidsthrough a type II fatty acid biosynthesis pathway. For example, themicroorganism can be a microalga, but can also be a microorganism thatnormally possesses a type I fatty acid biosynthetic pathway (e.g., anoil producing yeast) into which type two genetic machinery has beenintroduced using genetic engineering techniques. The microorganism canbe a heterotroph, and in a specific embodiment, an obligate heterotroph.Where the microalga is used, the microalga may be a species ofPrototheca or Chlorella. Illustrative species include Protothecawickerhamii, Prototheca stagnora, Prototheca portoricensis, Protothecamoriformis, Prototheca zopfii, Chlorella kessleri, Chlorellaluteoviridis Chlorella protothecoides, and Chlorella vulgaris. In orderto be able to use sucrose feedstocks such as sugar cane juice and othersdescribed herein, the recombinant cell can include recombinant nucleicacids that include a sucrose invertase gene so as to express an activesucrose invertase. The sucrose invertase may be secreted by themicroorganism into the medium.

Cultivation can be heterotrophic; e.g., performed in a bioreactor usinga fixed carbon source such as glucose or sucrose. The cultivation may becontinued until the cell reaches at least 50%, at least 60%, at least70%, or 50 to 90% triglyceride by dry cell weight. This may entailcultivation using limiting nitrogen, as described infra.

The oil produced by the cell can be extracted from the cell. In anembodiment, the oil comprises less than 500, 50, or 5 ppm of coloredmolecules. Optionally, the oil is analyzed for its fatty acid profile;e.g., by LC-MS. The oil can also have one or more of the properties ofthe oil of Example 19, tables 60-63.

In a specific embodiment, the recombinant cell comprises nucleic acidsoperable to decrease or eliminate the expression of a β-ketoacyl-ACPsynthase II encoded by a KASII gene, and to express a product of anexogenous gene encoding an acyl-ACP thioesterase. As a result, the cellcan produce an oil with a fatty acid profile characterized by having atleast 40, 50, 60, or 70% C16 fatty acids (e.g., palmitic acid). Thus,the oil can have a fatty acid distribution shifted towards shorter chainlengths. The shift in the fatty acid distribution can be characterizedby a reduced mean fatty acid length o9r other statisticalcharacterization of the distribution. For example, to calculate meanfatty acid length, the percent of each detectable fatty acid making upthe triglycerides is multiplied by the number of carbons in the fattyacid and the sum of the products is divided by 100. The exogenous geneencoding the acyl-ACP thioesterase can produce an active acyl-ACPthioesterase having greater activity in hydrolysis of C8-C16 fatty acylchains than a native acyl-ACP-thioesterase of the cell. The exogenousgene encoding an acyl-ACP thioesterase can interrupt the KASII gene. Inthis way, the insertion of the acyl-ACP thioesterase can also eliminateexpression of the Pβ-ketoacyl-ACP synthase II in one step. See Examples15 and 16.

In another specific embodiment, the recombinant cell comprises nucleicacids operable to decrease or eliminate the expression of an enzymeencoded by one or more genes that encode a β-ketoacyl-ACP synthase I. Asa result, the oil produced has a fatty acid profile characterized by adistribution of fatty acid chain lengths that is shorter than acomparable cell lacking the recombinant nucleic acids. This may beexpressed as a reduced mean fatty acid chain length. The recombinantcell can include nucleic acids operable to decrease or eliminate theexpression of a fatty acid destaurase encoded by at least one FAD geneand to express a product of a stearoyl-ACP desaturase exogenous geneencoding an active stearoyl ACP desaturase. Optionally, the nucleicacids are operable to decrease or eliminate the expression of a fattyacid destaurase encoded by multiple copies (e.g., alleles) of a fattyacid desaturase gene. In a specific embodiment, the stearoyl-ACPdesaturase exogenous gene is recombined into a locus within the codingregion of the fatty acid desaturase gene. As a result, the oil producedcan have an elevated level of oleic acid compared to that produced by acomparable cell lacking the nucleic acids. The oleic acid comprises atleast 50, 60, 70, 80, or 90% of the fatty acids in the fatty acidprofile. See Example 10.

In another specific embodiment, the recombinant cell comprises nucleicacids operable to express a product of a β-ketoacyl-ACP synthase IIexogenous gene encoding an active β-ketoacyl-ACP synthase II. As aresult, the oil produced can be characterized by a fatty acid profileelevated in 18:1 fatty acids and reduced in C16 fatty acids as a resultof the recombinant nucleic acids. See Example 13, in whichoverexpression of a KASII gene increased the percentage of C18 fattyacids from about 68% in the untransformed cells to about 84%. In relatedembodiments, the increase is greater than 70%, from 75-85%, or from70-90%.

In another specific embodiment, the recombinant cell comprises nucleicacids operable to decrease or eliminate the expression of an enzymeencoded by one or more genes that encode a stearoyl ACP desaturase byRNA interference. As a result, the oil produced can have a fatty acidprofile characterized by an increase in 18:0 fatty acids. The 18:0 fattyacids can be at least 50, 60, 70, 80, or 90% of the fatty acids in theprofile. See Example 12.

In another specific embodiment, the cell comprises recombinant nucleicacids operable to decrease or eliminate the expression of two copies ofa gene (e.g. two alleles) encoding a β-ketoacyl-ACP synthase I,β-ketoacyl-ACP synthase II, stearoyl ACP desaturase, or fatty aciddesaturase. See Example 14, in which an endogenous KASI allele wasknocked out in Prototheca. As a result, an increase was observed in thepercentage of total C14 fatty acids by about 35% to 400% and thepercentage of C16 fatty acids by about 30 to 50% due to disruption of anendogenous KASI.

In another specific embodiment, the cell comprises recombinant nucleicacids operable to express a product of a fatty acid desaturase exogenousgene encoding an active a ω-3 fatty acid desaturase and/or a ω-6 oleatedesaturase. As a result, elevated levels of linoleic acid, linolenicacid, or both can be produced by the cell, and detected in the fattyacid profile of the cell lipids. For example, the cell can have at least10, 20, 30, 40, or 50% linoleic acid, linolenic acid, or both. Forexample, a recombinant A15 desaturase enzyme may be expressed as inExample 11. As a result, C18:3 fatty acids (i.e., linolenic acid), canbe increased from about 2 to 17 fold, or more.

In another embodiment, a cell of a recombinant microorganism iscultivated. The cell includes recombinant nucleic acids that operate toexpress a product of an exogenous gene encoding an active oleate12-hydroxylase, so as to synthesize the ricinoleic acid. This gene maybe present in any of the aforementioned embodiments. See Example 7. Apreferred substrate for 12-hydroxylase is oleic acid. Thus, in apreferred embodiment, a higher yield of ricinoleic acid may be obtainedby inclusion in the cell of recombinant nucleic acids that operate toincrease oleic acid production. Without limitation, the cell comprisesrecombinant nucleic acids operable to express a product of an exogenousgene encoding an active stearoyl ACP desaturase and decrease oreliminate the expression of an enzyme encoded by one or more genes thatencode a fatty acid desaturase; or express a product of an exogenousgene encoding an active β-ketoacyl-ACP synthase I and express a productof an exogenous gene encoding an active acyl-ACP thioesterase.

In accordance with any of the embodiments of the invention, the oil canbe extracted and further processed by one or more of refining,bleaching, deodorizing, metathesis, transesterification, hydrogenation,hydrolysis, hydrogenation, deoxygenation, hydrocracking, isomerization,hydroxylation, interesterification, amidation, sulfonation, andsulfurization. The oil may be processed, for example, to create a foodoil, fatty acids, a fatty alcohol, a lubricant, a soap, a fatty acidester, a fatty acid ethoxylate, a fatty amine, an akyl chloride, a fattyalcohol ethoxylate, a fatty alcohol sulfate, a fatty acid alkanolamide,a sulfonated oil, or a sulfurized oil, diesel, jet gasoline, or ablendstock or additive, a lubricant, or a paint.

Any of the embodiments mentioned herein can be useful as a food or foodoil. The whole organism can be incorporated into a food. The organismcan be intact, partly lysed, mostly lysed or entirely lysed. Methods forpreparing and using oleaginous organisms in food is taught inWO2011/150411, WO2010/12093, WO2011130578, and WO2011/130576.Alternately, the extracted and optionally purified oil from the organismcan be used as food oil, including as a food oil ingredient in preparedfoods such as spreads, sauces, confections, and frozen confections. In aspecific embodiment, the oleaginous cells or food oil comprise 50-70%C18:0 and 20-40% 18:1 (e.g., oleate). In another specific embodiment,the oleaginous cells or food oil comprises 50-70% C16:0 and 20-40% 18:1(e.g., oleate).

This detailed description of the invention is divided into sections forthe convenience of the reader. Section I provides definitions of termsused herein. Section II provides a description of culture conditionsuseful in the methods of the invention. Section III provides adescription of genetic engineering methods and materials. Section IVprovides a description of genetic engineering to enable sucroseutilization. Section V provides a description of genetic engineering tomodify lipid biosynthesis. Section VI describes methods for making fuelsand chemicals. Section VII discloses examples and embodiments of theinvention. The detailed description of the invention is followed byexamples that illustrate the various aspects and embodiments of theinvention.

I. DEFINITIONS

Unless defined otherwise, all technical and scientific terms used hereinhave the meaning commonly understood by a person skilled in the art towhich this invention belongs. As used herein, the following terms havethe meanings ascribed to them unless specified otherwise.

“Active in microalgae” refers to a nucleic acid that is functional inmicroalgae. For example, a promoter that has been used to drive anantibiotic resistance gene to impart antibiotic resistance to atransgenic microalgae is active in microalgae.

“Area Percent” refers to the area of peaks observed using FAME GC/FIDdetection methods in which every fatty acid in the sample is convertedinto a fatty acid methyl ester (FAME) prior to detection. For example, aseparate peak is observed for a fatty acid of 14 carbon atoms with nounsaturation (C14:0) compared to any other fatty acid such as C14:1. Thepeak area for each class of FAME is directly proportional to its percentcomposition in the mixture and is calculated based on the sum of allpeaks present in the sample (i.e. [area under specific peak/total areaof all measured peaks]×100). When referring to lipid profiles of oilsand cells of the invention, “at least 4% C8-C14” means that at least 4%of the total fatty acids in the cell or in the extracted glycerolipidcomposition have a chain length that includes 8, 10, 12 or 14 carbonatoms.

“Axenic” is a culture of an organism free from contamination by otherliving organisms.

“Biodiesel” is a biologically produced fatty acid alkyl ester suitablefor use as a fuel in a diesel engine.

“Biomass” is material produced by growth and/or propagation of cells.Biomass may contain cells and/or intracellular contents as well asextracellular material, includes, but is not limited to, compoundssecreted by a cell.

“Bioreactor” is an enclosure or partial enclosure in which cells arecultured, optionally in suspension.

“Cellulosic material” is a biological material comprising cellulose andoptionally hemicellulose. As such it is digestible to sugars such asglucose and xylose, and optionally may comprise additional compoundssuch as disaccharides, oligosaccharides, lignin, furfurals and othercompounds. Nonlimiting examples of sources of cellulosic materialinclude sugar cane bagasses, sugar beet pulp, corn stover, wood chips,sawdust and switchgrass.

“Co-culture”, and variants thereof such as “co-cultivate” and“co-ferment”, refer to cultivating two or more types of cells in thesame bioreactor. The two or more types of cells may both bemicroorganisms, such as microalgae, or may be a microalgal cell culturedwith a different cell type.

“Colored molecules” or “color generating impurities” as used hereinrefer to any compound that imparts a color to the extracted oil.“Colored molecules” or “color generating impurities” include forexample, chlorophyll a, chlorophyll b, lycopenes, tocopherols,campesterols, tocotrienols, and carotenoids, such as beta carotene,luteins, zeaxanthin, astaxanthin. These molecules are preferably presentin the microbial biomass or the extracted oil at a concentration of nomore than 500 ppm, no more than 250 ppm, no more than 100 ppm, no morethan 75 ppm, or no more than 25 ppm. In other embodiments, the amount ofchlorophyll that is present in the microbial biomass or the extractedoil is less than 500 mg/kg, less than 100 mg/kg, less than 10 mg/kg,less than 1 mg·kg, less than 0.5 mg/kg, less than 0.1 mg/kg, less than0.05 mg/kg, or less than 0.01 mg/kg.

“Cultivated”, and variants thereof such as “cultured” and “fermented”,refer to the intentional fostering of growth (increases in cell size,cellular contents, and/or cellular activity) and/or propagation(increases in cell numbers) of one or more cells by use of selectedand/or controlled conditions. The combination of both growth andpropagation is termed “proliferation.” Examples of selected and/orcontrolled conditions include the use of a defined medium (with knowncharacteristics such as pH, ionic strength, and carbon source),specified temperature, oxygen tension, carbon dioxide levels, and growthin a bioreactor. “Cultivated” does not refer to the growth orpropagation of microorganisms in nature or otherwise without humanintervention; for example, natural growth of an organism that ultimatelybecomes fossilized to produce geological crude oil is not cultivation.

“Desaturase” refers to an enzyme in the lipid synthesis pathwayresponsible for the introduction of double bonds (unsaturation) into thefatty acid chains of triacylglyceride molecules. Examples include butare not limited to stearoyl-Acyl carrier protein desaturase (SAD) andfatty acid desaturase (FAD), also known as fatty acyl desaturase.

“Expression vector” or “expression construct” or “plasmid” or“recombinant DNA construct” is a vehicle for introducing a nucleic acidinto a host cell. The nucleic acid can be one that has been generatedvia human intervention, including by recombinant means or directchemical synthesis, with a series of specified nucleic acid elementsthat permit transcription and/or translation of a particular nucleicacid. The expression vector can be part of a plasmid, virus, or nucleicacid fragment, or other suitable vehicle. Typically, the expressionvector includes a nucleic acid to be transcribed operably linked to apromoter.

“Exogenous gene” is a nucleic acid that codes for the expression of anRNA and/or protein that has been introduced into a cell (e.g. bytransformation/transfection), and is also referred to as a “transgene”.A cell comprising an exogenous gene may be referred to as a recombinantcell, into which additional exogenous gene(s) may be introduced. Theexogenous gene may be from a different species (and so heterologous), orfrom the same species (and so homologous), relative to the cell beingtransformed. Thus, an exogenous gene can include a homologous gene thatoccupies a different location in the genome of the cell or is underdifferent control, relative to the endogenous copy of the gene. Anexogenous gene may be present in more than one copy in the cell. Anexogenous gene may be maintained in a cell as an insertion into thegenome (nuclear or plastid) or as an episomal molecule.

“Exogenously provided” refers to a molecule provided to the culturemedia of a cell culture.

Depending on the context, “fatty acids” shall mean free fatty acids,fatty acid salts, or fatty acyl moieties in a glycerolipid.

“Fixed carbon source” is a molecule(s) containing carbon, typically anorganic molecule, that is present at ambient temperature and pressure insolid or liquid form in a culture media that can be utilized by amicroorganism cultured therein. Accordingly, carbon dioxide is not afixed carbon source.

“Heterotrophic” as it pertains to culture conditions is culturing in thesubstantial absence of light while utilizing or metabolizing a fixedcarbon source.

“Homogenate” is biomass that has been physically disrupted.

“Hydrogen:carbon ratio” is the ratio of hydrogen atoms to carbon atomsin a molecule on an atom-to-atom basis. The ratio may be used to referto the number of carbon and hydrogen atoms in a hydrocarbon molecule.For example, the hydrocarbon with the highest ratio is methane CH₄(4:1).

“Inducible promoter” is a promoter that mediates transcription of anoperably linked gene in response to a particular stimulus. Examples ofsuch promoters may be promoter sequences that are induced in conditionsof changing pH or nitrogen levels.

“In operable linkage” is a functional linkage between two nucleic acidsequences, such a control sequence (typically a promoter) and the linkedsequence (typically a sequence that encodes a protein, also called acoding sequence). A promoter is in operable linkage with an exogenousgene if it can mediate transcription of the gene.

“Lipid modification enzyme” refers to an enzyme that alters the covalentstructure of a lipid or can otherwise lead to an altered fatty acidprofile in a cell. Examples of lipid modification enzymes include alipase, a fatty acyl-ACP thioesterase, a fatty acyl-CoA/aldehydereductase, a fatty acyl-CoA reductase, a fatty aldehyde reductase, adesaturase, including a stearoyl acyl carrier protein desaturase (SAD)and a fatty acyl destaurase (FAD), and a fatty aldehyde decarbonylase.

“Lipid pathway enzyme” is any enzyme that plays a role in lipidmetabolism, i.e., either lipid synthesis, modification, or degradation,and any proteins that chemically modify lipids, as well as carrierproteins.

“Lipid profile” or “glycerolipid profile” refers to the distribution offatty acids in a cell or oil derived from a cell in terms of chainlength and/or saturation pattern. In this context the saturation patterncan comprise a measure of saturated versus unsaturated acid or a moredetailed analysis of the distribution of the positions of double bondsin the various fatty acids of a cell.

“Lysis” is the breakage of the plasma membrane and optionally the cellwall of a biological organism sufficient to release at least someintracellular content, often by mechanical, chemical, viral or osmoticmechanisms that compromise its integrity.

“Lysing” is the process of lysis.

“Microalgae” is a microbial organism that contains a chloroplast orplastid, and optionally that is capable of performing photosynthesis, ora prokaryotic microbial organism capable of performing photosynthesis.Microalgae include obligate photoautotrophs, which cannot metabolize afixed carbon source as energy, as well as heterotrophs, which can livesolely off of a fixed carbon source. Microalgae include unicellularorganisms that separate from sister cells shortly after cell division,such as Chlamydomonas, as well as microbes such as, for example, Volvox,which is a simple multicellular photosynthetic microbe of two distinctcell types. Microalgae include cells such as Chlorella, Dunaliella, andPrototheca. Microalgae also include other microbial photosyntheticorganisms that exhibit cell-cell adhesion, such as Agmenellum, Anabaena,and Pyrobotrys. Microalgae also include obligate heterotrophicmicroorganisms that have lost the ability to perform photosynthesis,such as certain dinoflagellate algae species and species of the genusPrototheca.

“Mid chain”, as used herein in the context of fatty acids, refers to aC10-C16 fatty acid. “Short chain”, in this context, refers to C6-C10fatty acids, while “long chain” refers to C17 or longer fatty acids.These boundaries are not intended to be precisely defined, unlessotherwise indicated.

A “natural oil” shall mean a predominantly triglyceride oil obtainedfrom an organism, where the oil has not undergone blending with anothernatural or synthetic oil, or fractionation so as to substantially alterthe fatty acid profile of the triglyceride. Here, the term“fractionation” means removing material from the oil in a way thatchanges its fatty acid profile relative to the profile produced by theorganism, however accomplished. A natural oil encompasses such an oilobtained from an organism, where the oil has undergone minimalprocessing, including refining, bleaching and/or degumming, that doesnot substantially change its triglyceride profile. A natural oil canalso be a “noninteresterified natural oil”, which means that the naturaloil has not undergone a process in which fatty acids have beenredistributed in their acyl linkages to glycerol and remain essentiallyin the same configuration as when recovered from the organism.

“Naturally co-expressed” with reference to two proteins or genes meansthat the proteins or their genes are co-expressed naturally in a tissueor organism from which they are derived, e.g., because the genesencoding the two proteins are under the control of a common regulatorysequence or because they are expressed in response to the same stimulus.

“Osmotic shock” is the rupture of cells in a solution following a suddenreduction in osmotic pressure. Osmotic shock is sometimes induced torelease cellular components of such cells into a solution.

“Polysaccharide-degrading enzyme” is any enzyme capable of catalyzingthe hydrolysis, or saccharification, of any polysaccharide. For example,cellulases catalyze the hydrolysis of cellulose.

“Polysaccharides” or “glycans” are carbohydrates made up ofmonosaccharides joined together by glycosidic linkages. Cellulose is apolysaccharide that makes up certain plant cell walls. Cellulose can bedepolymerized by enzymes to yield monosaccharides such as xylose andglucose, as well as larger disaccharides and oligosaccharides.

“Promoter” is a nucleic acid control sequence that directs transcriptionof a nucleic acid. As used herein, a promoter includes necessary nucleicacid sequences near the start site of transcription, such as, in thecase of a polymerase II type promoter, a TATA element. A promoter alsooptionally includes distal enhancer or repressor elements, which can belocated as much as several thousand base pairs from the start site oftranscription.

“Recombinant” is a cell, nucleic acid, protein or vector, that has beenmodified due to the introduction of an exogenous nucleic acid or thealteration of a native nucleic acid. Thus, e.g., recombinant cells canexpress genes that are not found within the native (non-recombinant)form of the cell or express native genes differently than those genesare expressed by a non-recombinant cell. Recombinant cells can, withoutlimitation, include recombinant nucleic acids that encode for a geneproduct or for suppression elements such as mutations, knockouts,antisense, interfering RNA (RNAi) or dsRNA that reduce the levels ofactive gene product in a cell. A “recombinant nucleic acid” is a nucleicacid originally formed in vitro, in general, by the manipulation ofnucleic acid, e.g., using polymerases, ligases, exonucleases, andendonucleases, or otherwise is in a form not normally found in nature.Recombinant nucleic acids may be produced, for example, to place two ormore nucleic acids in operable linkage. Thus, an isolated nucleic acidor an expression vector formed in vitro by ligating DNA molecules thatare not normally joined in nature, are both considered recombinant forthe purposes of this invention. Once a recombinant nucleic acid is madeand introduced into a host cell or organism, it may replicate using thein vivo cellular machinery of the host cell; however, such nucleicacids, once produced recombinantly, although subsequently replicatedintracellularly, are still considered recombinant for purposes of thisinvention. Similarly, a “recombinant protein” is a protein made usingrecombinant techniques, i.e., through the expression of a recombinantnucleic acid.

“Renewable diesel” is a mixture of alkanes (such as C10:0, C12:0, C14:0,C16:0 and C18:0) produced from a natural oil; e.g., throughhydrogenation and deoxygenation of lipids.

“Saccharification” is a process of converting biomass, usuallycellulosic or lignocellulosic biomass, into monomeric sugars, such asglucose and xylose. “Saccharified” or “depolymerized” cellulosicmaterial or biomass refers to cellulosic material or biomass that hasbeen converted into monomeric sugars through saccharification.

“Species of furfural” is 2-furancarboxaldehyde or a derivative thatretains the same basic structural characteristics.

In connection with transformation of a strain to create a recombinantstrain in accordance with embodiments herein (and not necessarily todiscussions of prior art), “stable” or “stably integrated” shall meanthat the recombinant nucleic acids are retained by the cells of thestrain for at least 10 generations. For example, where a recombinantstrain has a selectable marker that enables cultivation in the presenceof a selection pressure, the recombinant nucleic acids are retainedafter 10 generations of cultivation in the absence of the selectionpressure.

“Sucrose utilization gene” is a gene that, when expressed, aids theability of a cell to utilize sucrose as an energy source. Proteinsencoded by a sucrose utilization gene are referred to herein as “sucroseutilization enzymes” and include sucrose transporters, sucroseinvertases, and hexokinases such as glucokinases and fructokinases.

II. CULTIVATION

The present invention generally relates to cultivation ofmicroorganisms, and particularly oleaginous microorganisms having a typeII fatty acid biosynthesis pathway, such as microalgae to producetriglycerides. In an embodiment, the microorganisms are obligateheterotrophs. The microorganisms may be recombinant microorganims based,for example, of the genetic engineering methods disclosed infra. For theconvenience of the reader, this section is subdivided into subsections.Subsection 1 describes species and strains of microorganisms. Subsection2 describes bioreactors useful for cultivation. Subsection 3 describesmedia for cultivation. Subsection 4 describes oil production inaccordance with illustrative cultivation methods of the invention.

1. Microogansim Species and Strains

Although the illustrative embodiments presented below are applicable tonumerous microorganisms, Prototheca is a preferred microorganism for usein the production of lipid. Importantly, the genetic engineering methodsdescribed herein with Prototheca as an example are applicable to othermicroorganisms (e.g., Chlorella sorokiniana, Chlorella vulgari,sChlorella ellipsoidea, Chlorella kessleri, Dunaliella tertiolecta,Volvox carteri, Haematococcus pluvialis, Closteriumperacerosum-strigosum-littorale complex, Dunaliella viridis, Dunaliellasalina, Gonium pectorale, Phaeodactylum tricornutum, Chaetoceros,Cylindrotheca fusiformis, Amphidinium sp., Symbiodiniummicroadriacticum, Nannochloropsis, Cyclotella cryptica, Naviculasaprophila, or Thalassiosira pseudonana).

Lipid or oil obtained from an obligate heterotrophic microalgae such asPrototheca can be generally low in pigment (e.g., low to undetectablelevels of chlorophyll and certain carotenoids, for example less than500, 50 or 5 ppm, of colored molecules, color-generating impurities, orthe sum of chlorophyll and carotenoid concentrations) and in any eventcontains much less pigment than lipid from other microalgae. Moreover,recombinant Prototheca cells provided by the invention can be used toproduce lipid in greater yield and efficiency, and with reduced cost,relative to the production of lipid from other microorganisms.Illustrative Prototheca strains for use in the methods of the inventioninclude In addition, this microalgae grows heterotrophically and can begenetically engineered as Prototheca wickerhamnii, Prototheca stagnora(including UTEX 327), Prototheca portoricensis, Prototheca moriformis(including UTEX strains 1441, 1435), and Prototheca zopfii. Species ofthe genus Prototheca are obligate heterotrophs.

Considerations affecting the selection of microorganisms for use inembodiments of the invention include, in addition to production ofsuitable lipids or hydrocarbons for production of oils, fuels, andoleochemicals: (1) high lipid content as a percentage of cell weight;(2) ease of growth; (3) ease of genetic engineering; and (4) ease ofbiomass processing. In particular embodiments, the wild-type orgenetically engineered microorganism yields cells that are at least 40%,at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, orat least 70% or more lipid. In other particular embodiments, thewild-type or genetically engineered microorganism yields cells thatcomprise between 40 and 80% or 50 and 90% triglyceride. Preferredorganisms grow heterotrophically (on sugars in the absence of light).

Examples of algae that can be used to practice the present inventioninclude, but are not limited to the following algae listed in Table 1.

TABLE 1 Examples of algae. Achnanthes orientalis, Agmenellum, Amphiprorahyaline, Amphora coffeiformis, Amphora coffeiformis linea, Amphoracoffeiformis punctata, Amphora coffeiformis taylori, Amphoracoffeiformis tenuis, Amphora delicatissima, Amphora delicatissimacapitata, Amphora sp., Anabaena, Ankistrodesmus, Ankistrodesmusfalcatus, Boekelovia hooglandii, Borodinella sp., Botryococcus braunii,Botryococcus sudeticus, Carteria, Chaetoceros gracilis, Chaetocerosmuelleri, Chaetoceros muelleri subsalsum, Chaetoceros sp., Chlorellaanitrata, Chlorella Antarctica, Chlorella aureoviridis, Chlorellacandida, Chlorella capsulate, Chlorella desiccate, Chlorellaellipsoidea, Chlorella emersonii, Chlorella fusca, Chlorella fusca var.vacuolata, Chlorella glucotropha, Chlorella infusionum, Chlorellainfusionum var. actophila, Chlorella infusionum var. auxenophila,Chlorella kessleri, Chlorella lobophora (strain SAG 37.88), Chlorellaluteoviridis, Chlorella luteoviridis var. aureoviridis, Chlorellaluteoviridis var. lutescens, Chlorella miniata, Chlorella minutissima,Chlorella mutabilis, Chlorella nocturna, Chlorella parva, Chlorellaphotophila, Chlorella pringsheimii, Chlorella protothecoides (includingany of UTEX strains 1806, 411, 264, 256, 255, 250, 249, 31, 29, 25, andCCAP strains 211/17 and 211/8d), Chlorella protothecoides var.acidicola, Chlorella regularis, Chlorella regularis var. minima,Chlorella regularis var. umbricata, Chlorella reisiglii, Chlorellasaccharophila, Chlorella saccharophila var. ellipsoidea, Chlorellasalina, Chlorella simplex, Chlorella sorokiniana, Chlorella sp.,Chlorella sphaerica, Chlorella stigmatophora, Chlorella vanniellii,Chlorella vulgaris, Chlorella vulgaris, Chlorella vulgaris f. tertia,Chlorella vulgaris var. autotrophica, Chlorella vulgaris var. viridis,Chlorella vulgaris var. vulgaris, Chlorella vulgaris var. vulgaris f.tertia, Chlorella vulgaris var. vulgaris f. viridis, Chlorellaxanthella, Chlorella zofingiensis, Chlorella trebouxioides, Chlorellavulgaris, Chlorococcum infusionum, Chlorococcum sp., Chlorogonium,Chroomonas sp., Chrysosphaera sp., Cricosphaera sp., Cryptomonas sp.,Cyclotella cryptica, Cyclotella meneghiniana, Cyclotella sp., Dunaliellasp., Dunaliella bardawil, Dunaliella bioculata, Dunaliella granulate,Dunaliella maritime, Dunaliella minuta, Dunaliella parva, Dunaliellapeircei, Dunaliella primolecta, Dunaliella salina, Dunaliella terricola,Dunaliella tertiolecta, Dunaliella viridis, Dunaliella tertiolecta,Eremosphaera viridis, Eremosphaera sp., Ellipsoidon sp., Euglena,Franceia sp., Fragilaria crotonensis, Fragilaria sp., Gleocapsa sp.,Gloeothamnion sp., Hymenomonas sp., Isochrysis aff. galbana, Isochrysisgalbana, Lepocinclis, Micractinium, Micractinium (UTEX LB 2614),Monoraphidium minutum, Monoraphidium sp., Nannochloris sp.,Nannochloropsis salina, Nannochloropsis sp., Navicula acceptata,Navicula biskanterae, Navicula pseudotenelloides, Navicula pelliculosa,Navicula saprophila, Navicula sp., Nephrochloris sp., Nephroselmis sp.,Nitschia communis, Nitzschia alexandrina, Nitzschia communis, Nitzschiadissipata, Nitzschia frustulum, Nitzschia hantzschiana, Nitzschiainconspicua, Nitzschia intermedia, Nitzschia microcephala, Nitzschiapusilla, Nitzschia pusilla elliptica, Nitzschia pusilla monoensis,Nitzschia quadrangular, Nitzschia sp., Ochromonas sp., Oocystis parva,Oocystis pusilla, Oocystis sp., Oscillatoria limnetica, Oscillatoriasp., Oscillatoria subbrevis, Pascheria acidophila, Pavlova sp., Phagus,Phormidium, Platymonas sp., Pleurochrysis carterae, Pleurochrysisdentate, Pleurochrysis sp., Prototheca wickerhamii, Prototheca stagnora,Prototheca portoricensis, Prototheca moriformis, Prototheca zopfii,Pyramimonas sp., Pyrobotrys, Sarcinoid chrysophyte, Scenedesmus armatus,Spirogyra, Spirulina platensis, Stichococcus sp., Synechococcus sp.,Tetraedron, Tetraselmis sp., Tetraselmis suecica, Thalassiosiraweissflogii, and Viridiella fridericiana

2. Bioreactor

Microrganisms are cultured both for purposes of conducting geneticmanipulations and for production of hydrocarbons (e.g., lipids, fattyacids, aldehydes, alcohols, and alkanes). The former type of culture isconducted on a small scale and initially, at least, under conditions inwhich the starting microorganism can grow. Culture for purposes ofhydrocarbon production is usually conducted on a large scale (e.g.,10,000 L, 40,000 L, 100,000 L or larger bioreactors) in a bioreactor.Microalgae, including Prototheca species are typically cultured in themethods of the invention in liquid media within a bioreactor. Typically,the bioreactor does not allow light to enter.

The bioreactor or fermentor is used to culture microalgal cells throughthe various phases of their physiological cycle. Bioreactors offer manyadvantages for use in heterotrophic growth and propagation methods. Toproduce biomass, microalgae are preferably fermented in large quantitiesin liquid, such as in suspension cultures. Bioreactors such as steelfermentors can accommodate very large culture volumes (40,000 liter andgreater capacity bioreactors are used in various embodiments of theinvention). Bioreactors also typically allow for the control of cultureconditions such as temperature, pH, oxygen tension, and carbon dioxidelevels. For example, bioreactors are typically configurable, forexample, using ports attached to tubing, to allow gaseous components,like oxygen or nitrogen, to be bubbled through a liquid culture. Otherculture parameters, such as the pH of the culture media, the identityand concentration of trace elements, and other media constituents canalso be more readily manipulated using a bioreactor.

Bioreactors equipped with devices such as spinning blades and impellers,rocking mechanisms, stir bars, means for pressurized gas infusion can beused to subject cultures to mixing. Mixing may be continuous orintermittent. For example, in some embodiments, a turbulent flow regimeof gas entry and media entry is not maintained for reproduction of cellsuntil a desired increase in number of said cells has been achieved.

Bioreactor ports can be used to introduce, or extract, gases, solids,semisolids, and liquids, into the bioreactor chamber containing themicroalgae. While many bioreactors have more than one port (for example,one for media entry, and another for sampling), it is not necessary thatonly one substance enter or leave a port. For example, a port can beused to flow culture media into the bioreactor and later used forsampling, gas entry, gas exit, or other purposes. Preferably, a samplingport can be used repeatedly without altering compromising the axenicnature of the culture. A sampling port can be configured with a valve orother device that allows the flow of sample to be stopped and started orto provide a means of continuous sampling. Bioreactors typically have atleast one port that allows inoculation of a culture, and such a port canalso be used for other purposes such as media or gas entry.

Bioreactors ports allow the gas content of the culture of microalgae tobe manipulated. To illustrate, part of the volume of a bioreactor can begas rather than liquid, and the gas inlets of the bioreactor to allowpumping of gases into the bioreactor. Gases that can be beneficiallypumped into a bioreactor include air, oxygen, air/CO₂ mixtures, noblegases, such as argon, and other gases. Bioreactors are can be equippedto enable the user to control the rate of entry of a gas into thebioreactor. As noted above, increasing gas flow into a bioreactor can beused to increase mixing of the culture.

Increased gas flow affects the turbidity of the culture as well.Turbulence can be achieved by placing a gas entry port below the levelof the aqueous culture media so that gas entering the bioreactor bubblesto the surface of the culture. One or more gas exit ports allow gas toescape, thereby preventing pressure buildup in the bioreactor.Preferably a gas exit port leads to a “one-way” valve that preventscontaminating microorganisms from entering the bioreactor.

3. Media

Microbial culture media typically contains components such as a fixednitrogen source, a fixed carbon source, trace elements, optionally abuffer for pH maintenance, and phosphate (typically provided as aphosphate salt). Other components can include salts such as sodiumchloride, particularly for seawater microalgae. Nitrogen sources includeorganic and inorganic nitrogen sources, including, for example, withoutlimitation, molecular nitrogen, nitrate, nitrate salts, ammonia (pure orin salt form, such as, (NH₄)₂SO₄ and NH₄OH), protein, soybean meal,cornsteep liquor, and yeast extract. Examples of trace elements includezinc, boron, cobalt, copper, manganese, and molybdenum in, for example,the respective forms of ZnCl₂, H₃BO₃, CoCl₂.6H₂O, CuCl₂.2H₂O, MnCl₂.4H₂Oand (NH₄)₆Mo₇O₂₄.4H₂O.

Microorganisms useful in accordance with the methods of the presentinvention are found in various locations and environments throughout theworld. As a consequence of their isolation from other species and theirresulting evolutionary divergence, the particular growth medium foroptimal growth and generation of lipid and/or hydrocarbon constituentscan be difficult to predict. In some cases, certain strains ofmicroorganisms may be unable to grow on a particular growth mediumbecause of the presence of some inhibitory component or the absence ofsome essential nutritional requirement required by the particular strainof microorganism.

Solid and liquid growth media are generally available from a widevariety of sources, and instructions for the preparation of particularmedia that is suitable for a wide variety of strains of microorganismscan be found, for example, online at http://www.utex.org/, a sitemaintained by the University of Texas at Austin, 1 University StationA6700, Austin, Tex., 78712-0183, for its culture collection of algae(UTEX). For example, various fresh water and salt water media includethose described in PCT Pub. No. 2008/151149, incorporated herein byreference.

In a particular example, Proteose Medium is suitable for axeniccultures, and a 1 L volume of the medium (pH ˜6.8) can be prepared byaddition of 1 g of proteose peptone to 1 liter of Bristol Medium.Bristol medium comprises 2.94 mM NaNO₃, 0.17 mM CaCl₂.2H₂O, 0.3 mMMgSO₄.7H₂O, 0.43 mM, 1.29 mM KH₂PO₄, and 1.43 mM NaCl in an aqueoussolution. For 1.5% agar medium, 15 g of agar can be added to 1 L of thesolution. The solution is covered and autoclaved, and then stored at arefrigerated temperature prior to use. Another example is the Protothecaisolation medium (PIM), which comprises 10 g/L postassium hydrogenphthalate (KHP), 0.9 g/L sodium hydroxide, 0.1 g/L magnesium sulfate,0.2 g/L potassium hydrogen phosphate, 0.3 g/L ammonium chloride, 10 g/Lglucose 0.001 g/L thiamine hydrochloride, 20 g/L agar, 0.25 g/L5-fluorocytosine, at a pH in the range of 5.0 to 5.2 (see Pore, 1973,App. Microbiology, 26: 648-649). Other suitable media for use with themethods of the invention can be readily identified by consulting the URLidentified above, or by consulting other organizations that maintaincultures of microorganisms, such as SAG, CCAP, or CCALA. SAG refers tothe Culture Collection of Algae at the University of Gottingen(Gottingen, Germany), CCAP refers to the culture collection of algae andprotozoa managed by the Scottish Association for Marine Science(Scotland, United Kingdom), and CCALA refers to the culture collectionof algal laboratory at the Institute of Botany (Trebofi, CzechRepublic). Additionally, U.S. Pat. No. 5,900,370 describes mediaformulations and conditions suitable for heterotrophic fermentation ofPrototheca species.

For oil production, selection of a fixed carbon source is important, asthe cost of the fixed carbon source must be sufficiently low to make oilproduction economical. Thus, while suitable carbon sources can include,for example, acetate, floridoside, fructose, galactose, glucuronic acid,glucose, glycerol, lactose, mannose, N-acetylglucosamine, rhamnose,sucrose, and/or xylose, selection of feedstocks containing thosecompounds is an important aspect of the methods of embodiments of theinvention. Suitable feedstocks useful in accordance with the methods ofthe invention can include, for example, black liquor, corn starch,depolymerized cellulosic material, milk whey, molasses, potato, sorghum,sucrose, sugar beet, sugar cane, rice, and wheat. Carbon sources canalso be provided as a mixture, such as a mixture of sucrose anddepolymerized sugar beet pulp. The one or more carbon source(s) can besupplied at a concentration of at least about 50 μM, at least about 100μM, at least about 500 μM, at least about 5 mM, at least about 50 mM,and at least about 500 mM, of one or more exogenously provided fixedcarbon source(s). Highly concentrated carbon sources as feedstock forfermentation are preferred. For example, in some embodiments glucoselevels of at least 300 g/L, at least 400 g/L, at least 500 g/L, or atleast 600 g/L or more of glucose level of the feedstock prior to thecultivation step, is added to a fed batch cultivation, in which thehighly concentrated fixed carbon source is fed to the cells over time asthe cells grow and accumulate lipid. In other embodiments, sucroselevels of at least 500 g/L, at least 600 g/L, at least 700 g/L, at least800 g/L or more of sucrose prior to the cultivation is added to a fedbatch cultivation, in which the highly concentrated fixed carbon sourceis fed to the cells over time as the cells grow and accumulate lipid.Non-limiting examples of highly concentrated fixed carbon source such assucrose include thick cane juice, sugar cane juice, sugar beet juice andmolasses. Carbon sources of particular interest for purposes of thepresent invention include cellulose (in a depolymerized form), glycerol,sucrose, and sorghum, each of which is discussed in more detal below.

In accordance with the present invention, microorganisms can be culturedusing depolymerized cellulosic biomass as a feedstock. Cellulosicbiomass (e.g., stover, such as corn stover) is inexpensive and readilyavailable; however, such feedstocks have been found to be inhibitory toyeast growth, and yeast cannot use the 5-carbon sugars produced fromcellulosic materials (e.g., xylose from hemi-cellulose). By contrast, atleast some microalgae can grow on processed cellulosic material.Cellulosic materials generally include about 40-60% cellulose; about20-40% hemicellulose; and 10-30% lignin.

Cellulosic materials include residues from herbaceous and woody energycrops, as well as agricultural crops, i.e., the plant parts, primarilystalks and leaves, not removed from the fields with the primary food orfiber product. Examples include agricultural wastes such as sugarcanebagasse, rice hulls, corn fiber (including stalks, leaves, husks, andcobs), wheat straw, rice straw, sugar beet pulp, citrus pulp, citruspeels; forestry wastes such as hardwood and softwood thinnings, andhardwood and softwood residues from timber operations; wood wastes suchas saw mill wastes (wood chips, sawdust) and pulp mill waste; urbanwastes such as paper fractions of municipal solid waste, urban woodwaste and urban green waste such as municipal grass clippings; and woodconstruction waste. Additional cellulosics include dedicated cellulosiccrops such as switchgrass, hybrid poplar wood, and miscanthus, fibercane, and fiber sorghum. Five-carbon sugars that are produced from suchmaterials include xylose.

Cellulosic materials can be treated to increase the efficiency withwhich the microbe can utilize the sugar(s) contained within thematerials. Embodiments of the invention provide methods for thetreatment of cellulosic materials after acid explosion so that thematerials are suitable for use in a heterotrophic culture of microbes(e.g., microalgae and oleaginous yeast). As discussed above,lignocellulosic biomass is comprised of various fractions, includingcellulose, a crystalline polymer of beta 1,4 linked glucose (asix-carbon sugar), hemicellulose, a more loosely associated polymerpredominantly comprised of xylose (a five-carbon sugar) and to a lesserextent mannose, galactose, arabinose, lignin, a complex aromatic polymercomprised of sinapyl alcohol and its derivatives, and pectins, which arelinear chains of an alpha 1,4 linked polygalacturonic acid. Because ofthe polymeric structure of cellulose and hemicellulose, the sugars(e.g., monomeric glucose and xylose) in them are not in a form that canbe efficiently used (metabolized) by many microbes. For such microbes,further processing of the cellulosic biomass to generate the monomericsugars that make up the polymers can be very helpful to ensuring thatthe cellulosic materials are efficiently utilized as a feedstock (carbonsource).

Celluose or cellulosic biomass is subjected to a process, termed“explosion”, in which the biomass is treated with dilute sulfuric (orother) acid at elevated temperature and pressure. This processconditions the biomass such that it can be efficiently subjected toenzymatic hydrolysis of the cellulosic and hemicellulosic fractions intoglucose and xylose monomers. The resulting monomeric sugars are termedcellulosic sugars. Cellulosic sugars can subsequently be utilized bymicroorganisms to produce a variety of metabolites (e.g., lipid). Theacid explosion step results in a partial hydrolysis of the hemicellulosefraction to constitutent monosaccharides. These sugars can be completelyliberated from the biomass with further treatment. In some embodiments,the further treatment is a hydrothermal treatment that includes washingthe exploded material with hot water, which removes contaminants such assalts. This step is not necessary for cellulosic ethanol fermentationsdue to the more dilute sugar concentrations used in such processes. Inother embodiments, the further treatment is additional acid treatment.In still other embodiments, the further treatment is enzymatichydrolysis of the exploded material. These treatments can also be usedin any combination. The type of treatment can affect the type of sugarsliberated (e.g., five carbon sugars versus six carbon sugars) and thestage at which they are liberated in the process. As a consequence,different streams of sugars, whether they are predominantly five-carbonor six-carbon, can be created. These enriched five-carbon or six-carbonstreams can thus be directed to specific microorganisms with differentcarbon utilization cabilities.

The methods of the present invention can involve fermentation to highercell densities than what is typically achieved in ethanol fermentation.Because of the higher densities of the cultures for heterotrophiccellulosic oil production, the fixed carbon source (e.g., the cellulosicderived sugar stream(s)) is preferably in a concentrated form. Theglucose level of the depolymerized cellulosic material is preferably atleast 300 g/liter, at least 400 g/liter, at least 500 g/liter or atleast 600 g/liter prior to the cultivation step, which is optionally afed batch cultivation in which the material is fed to the cells overtime as the cells grow and accumulate lipid. Thus, in order to generateand sustain the very high cell densities during the production oflignocellulosic oil, the carbon feedstock(s) can be delivered into theheterotrophic cultures in a highly concentrated form. However, anycomponent in the feedstream that is not a substrate for, and is notmetabolized by, the oleaginous microorganism will accumulate in thebioreactor, which can lead to problems if the component is toxic orinhibitory to production of the desired end product. While ligin andlignin-derived by-products, carbohydrate-derived byproducts such asfurfurals and hydroxymethyl furfurals and salts derived from thegeneration of the cellulosic materials (both in the explosion processand the subsequent neutralization process), and even non-metabolizedpentose/hexose sugars can present problems in ethanolic fermentations,these effects are amplified significantly in a process in which theirconcentration in the initial feedstock is high. To achieve sugarconcentrations in the 300 g/L range (or higher) for six-carbon sugarsthat may be used in large scale production of lignocellulosic oildescribed in the present invention, the concentration of these toxicmaterials can be 20 times higher than the concentrations typicallypresent in ethanolic fermentations of cellulosic biomass.

The explosion process treatment of the cellulosic material utilizessignificant amounts of sulfuric acid, heat and pressure, therebyliberating by-products of carbohydrates, namely furfurals andhydroxymethyl furfurals. Furfurals and hydroxymethyl furfurals areproduced during hydrolysis of hemicellulose through dehydration ofxylose into furfural and water. In some embodiments of the presentinvention, these by-products (e.g., furfurals and hydroxymethylfurfurals) are removed from the saccharified lignocellulosic materialprior to introduction into the bioreactor. In certain embodiments of thepresent invention, the process for removal of the by-products ofcarbohydrates is hydrothermal treatment of the exploded cellulosicmaterials. In addition, the present invention provides methods in whichstrains capable of tolerating compounds such as furfurals orhydroxymethyl furfurals are used for lignocellulosic oil production. Inanother embodiment, the present invention also provides methods andmicroorganisms that are not only capable of tolerating furfurals in thefermentation media, but are actually able to metabolize theseby-products during the production of lignocellulosic oil.

The explosion process also generates significant levels of salts. Forexample, typical conditions for explosion can result in conductivites inexcess of 5 mS/cm when the exploded cellulosic biomass is resuspended ata ratio of 10:1 water:solids (dry weight). In certain embodiments of thepresent invention, the diluted exploded biomass is subjected toenzymatic saccharification, and the resulting supernatant isconcentrated up to 25 fold for use in the bioreactor. The salt level (asmeasured by conductivity) in the concentrated sugar stream(s) can beunacceptably high (up to 1.5 M Na⁺ equivalents). Additional salts aregenerated upon neutralization of the exploded materials for thesubsequent enzymatic saccharification process as well. Embodiments ofthe present invention provides methods for removing these salts so thatthe resulting concentrated cellulosic sugar stream(s) can be used inheterotrophic processes for producing lignocellulosic oil. In someembodiments, the method of removing these salts is deionization withresins, such as, but not limited to, DOWEX Marathon MR3. In certainembodiments, the deionization with resin step occurs before sugarconcentration or pH adjustment and hydrothermal treatment of biomassprior to saccharification, or any combination of the preceding; in otherembodiments, the step is conducted after one or more of these processes.In other embodiments, the explosion process itself is changed so as toavoid the generation of salts at unacceptably high levels. For example,an alternative to sulfuric acid (or other acid) explosion of thecellulosic biomass is mechanical pulping to render the cellulosicbiomass receptive to enzymatic hydrolysis (saccharification). In stillother embodiments, native strains of microorganisms resistant to highlevels of salts or genetically engineered strains with resistance tohigh levels of salts are used.

A preferred embodiment for the process of preparing of explodedcellulosic biomass for use in heterotrophic lignocellulosic oilproduction using oleaginous microbes follows. A first step comprisesadjusting the pH of the resuspended exploded cellulosic biomass to therange of 5.0-5.3 followed by washing the cellulosic biomass three times.This washing step can be accomplished by a variety of means includingthe use of desalting and ion exchange resins, reverse omosis,hydrothermal treatment (as described above), or just repeatedresuspension and centrifugation in deionized water. This wash stepresults in a cellulosic stream whose conductivity is between 100-300μS/cm and the removal of significant amounts of furfurals andhydroxymethyl furfurals. Decants from this wash step can be saved toconcentrate five-carbon sugars liberated from the hemicellulosefraction. A second step comprises enzymatic saccharification of thewashed cellulosic biomass. In a preferred embodiment, Accellerase(Genencor) is used. A third step comprises the recovery of sugars viacentrifugation or decanting and rinsing of the saccharified biomass. Theresulting biomass (solids) is an energy dense, lignin rich componentthat can be used as fuel or sent to waste. The recovered sugar stream inthe centrifugation/decanting and rinse process is collected. A fourthstep comprises microfiltration to remove contaminating solids withrecovery of the permeate. A fifth step comprises a concentration stepwhich can be accomplished using a vacuum evaporator. This step canoptionally include the addition of antifoam agents such as P'2000(Sigma/Fluka), which is sometimes necessary due to the protein contentof the resulting sugar feedstock.

In another embodiment of the methods of the invention, the carbon sourceis glycerol, including acidulated and non-acidulated glycerol byproductfrom biodiesel transesterification. In one embodiment, the carbon sourceincludes glycerol and at least one other carbon source. In some cases,all of the glycerol and the at least one other fixed carbon source areprovided to the microorganism at the beginning of the fermentation. Insome cases, the glycerol and the at least one other fixed carbon sourceare provided to the microorganism simultaneously at a predeterminedratio. In some cases, the glycerol and the at least one other fixedcarbon source are fed to the microbes at a predetermined rate over thecourse of fermentation.

Some microalgae undergo cell division faster in the presence of glycerolthan in the presence of glucose (see PCT Pub. No. 2008/151149). In theseinstances, two-stage growth processes, in which cells are first fedglycerol to rapidly increase cell density and are then fed glucose toaccumulate lipids, can improve the efficiency with which lipids areproduced. The use of the glycerol byproduct of the transesterificationprocess can provide significant economic advantages when put back intothe production process. Other feeding methods are provided as well, suchas mixtures of glycerol and glucose. Feeding such mixtures also capturesthe same economic benefits. In addition, the invention provides methodsof feeding alternative sugars to microalgae such as sucrose in variouscombinations with glycerol.

In another embodiment of the methods of the invention, the carbon sourceis invert sugar. Invert sugar is less prone to crystallization comparedto sucrose and thus, can provide advantages for storage and in fed batchfermentation, which in the case of heterotrophic cultivation ofmicrobes, including microalgae, there is a need for concentrated carbonsource. In one embodiment, the carbon source is invert sugar, preferablyin a concentrated form, preferably at least 800 g/liter, at least 900g/liter, at least 1000 g/liter or at least 1100 g/liter prior to thecultivation step, which is optionally a fed batch cultivation. Theinvert sugar, preferably in a concentrated form, is fed to the cellsover time as the cells grow and accumulate lipid.

In another embodiment of the methods of the invention, the carbon sourceis sucrose, including a complex feedstock containing sucrose, such asthick cane juice from sugar cane processing. Because of the higherdensities of the cultures for heterotrophic oil production, the fixedcarbon source (e.g., sucrose, glucose, etc.) is preferably in aconcentrated form, preferably at least 500 g/liter, at least 600g/liter, at least 700 g/liter or at least 800 g/liter of the fixedcarbon source prior to the cultivation step, which is optionally a fedbatch cultivation in which the material is fed to the cells over time asthe cells grow and accumulate lipid. In some cases, the carbon source issucrose in the form of thick cane juice, preferably in a concentratedform, preferably at least 60% solids or about 770 g/liter sugar, atleast 70% solids or about 925 g/liter sugar, or at least 80% solids orabout 1125 g/liter sugar prior to the cultivation step, which isoptionally a fed batch cultivation. The concentrated thick cane juice isfed to the cells over time as the cells grow and accumulate lipid.

In one embodiment, the culture medium further includes at least onesucrose utilization enzyme. In some cases, the sucrose utilizationenzyme is a sucrose invertase. The sucrose invertase enzyme can be asecrectable sucrose invertase enzyme encoded by an exogenous sucroseinvertase gene expressed by the population of microorganisms. Thesecretable sucrose invertase can be secreted by the microorganisms intothe culture medium so as to convert sucrose in the medium to glucose andfructose for use by the microorganism. As described below, the sucroseinvertase can be recombinant, thereby imparting upon a microorganism theability to use pure or complex sucrose feedstocks as a fixed carbonsource for growth or oil production. In some cases, as described in moredetail in Section IV, below, the microalgae has been geneticallyengineered to express a sucrose utilization enzyme, such as a sucrosetransporter, a sucrose invertase, a hexokinase, a glucokinase, or afructokinase.

Complex feedstocks containing sucrose include waste molasses from sugarcane processing; the use of this low-value waste product of sugar caneprocessing can provide significant cost savings in the production ofhydrocarbons and other oils. Another complex feedstock containingsucrose that is useful in the methods of the invention is sorghum,including sorghum syrup and pure sorghum. Sorghum syrup is produced fromthe juice of sweet sorghum cane. Its sugar profile consists of mainlyglucose (dextrose), fructose and sucrose.

4. Oil Production

For the production of oil in accordance with the methods of theinvention, it is preferable to culture cells in the dark, as is thecase, for example, when using extremely large (40,000 liter and higher)fermentors that do not allow light to strike the culture. Heterotrophicspecies are grown and propagated for the production of oil in a mediumcontaining a fixed carbon source and in the absence of light; suchgrowth is known as heterotrophic growth.

As an example, an inoculum of lipid-producing microalgal cells areintroduced into the medium; there is a lag period (lag phase) before thecells begin to propagate. Following the lag period, the propagation rateincreases steadily and enters the log, or exponential, phase. Theexponential phase is in turn followed by a slowing of propagation due todecreases in nutrients such as nitrogen, increases in toxic substances,and quorum sensing mechanisms. After this slowing, propagation stops,and the cells enter a stationary phase or steady growth state, dependingon the particular environment provided to the cells. For obtaining lipidrich biomass, the culture is typically harvested well after then end ofthe exponential phase, which may be terminated early by allowingnitrogen or another key nutrient (other than carbon) to become depleted,forcing the cells to convert the carbon sources, present in excess, tolipid, an in particular, to triglcyeride. Culture condition parameterscan be manipulated to optimize total oil production, the combination oflipid species produced, and/or production of a specific oil.

Lipid production by cells disclosed herein can occur during the logphase or thereafter, including the stationary phase wherein nutrientsare supplied, or still available, to allow the continuation of lipidproduction in the absence of cell division.

Preferably, microorganisms grown using conditions described hereinand/or known in the art comprise at least about 20-30%, 30-40%, 40-50%,50-60%, 60-70%, or 80-90% by dry cell weight of triglyceride. Processconditions can be adjusted to increase the yield of lipids suitable fora particular use and/or to reduce production cost. For example, incertain embodiments, a microalgae is cultured in the presence of alimiting concentration of one or more nutrients, such as, for example,nitrogen, phosphorous, or sulfur, while providing an excess of fixedcarbon energy such as glucose. Nitrogen limitation tends to increasemicrobial lipid yield (a measure of the amount of lipid produced pergram of dry cell weight) over microbial lipid yield in a culture inwhich nitrogen is provided in excess. In particular embodiments, theincrease in lipid yield is at least about: 10%, 50%, 100%, 200%, or500%. The microbe can be cultured in the presence of a limiting amountof a nutrient for a portion of the total culture period or for theentire period. In particular embodiments, the nutrient concentration iscycled between a limiting concentration and a non-limiting concentrationat least twice during the total culture period. Lipid content of cellscan be increased by continuing the culture for increased periods of timewhile providing an excess of carbon, but limiting or no nitrogen.

In another embodiment, lipid yield is increased by culturing alipid-producing microbe (e.g., microalgae) in the presence of one ormore cofactor(s) for a lipid pathway enzyme (e.g., a coenzyme orprosthetic group of a fatty acid synthetic enzyme). Generally, theconcentration of the cofactor(s) is sufficient to increase microbiallipid (e.g., fatty acid) yield over microbial lipid yield in the absenceof the cofactor(s). In a particular embodiment, the cofactor(s) areprovided to the culture by including in the culture a microbe (e.g.,microalgae) containing an exogenous gene encoding the cofactor(s).Alternatively, cofactor(s) may be provided to a culture by including amicrobe (e.g., microalgae) containing an exogenous gene that encodes aprotein that participates in the synthesis of the cofactor. In certainembodiments, suitable cofactors include any vitamin required by a lipidpathway enzyme, such as, for example: biotin or pantothenate. Genesencoding cofactors suitable for use in the invention or that participatein the synthesis of such cofactors are well known and can be introducedinto microbes (e.g., microalgae), using constructs and techniques suchas those described above.

The specific examples of bioreactors, culture conditions, andheterotrophic growth and propagation methods described herein can becombined in any suitable manner to improve efficiencies of microbialgrowth and lipid and/or protein production.

Microalgal biomass with a high percentage of oil/lipid accumulation bydry weight has been generated using different methods of culture, whichare known in the art (see PCT Pub. No. 2008/151149). Microalgal biomassgenerated by the culture methods described herein and useful inaccordance with the present invention comprises at least 10% microalgaloil by dry weight. In some embodiments, the microalgal biomass comprisesat least 25%, 50%, 60%, 70% or at least 80% microalgal oil by dryweight. In some embodiments, the microalgal biomass contains from 10-90%microalgal oil, from 25-75% microalgal oil, from 40-75% microalgal oil,75-85%, or from 50-70% microalgal oil by dry weight.

The microalgal oil of the biomass described herein, or extracted fromthe biomass for use in the methods and compositions of the presentinvention can comprise glycerolipids with one or more distinct fattyacid ester side chains. Glycerolipids are comprised of a glycerolmolecule esterified to one, two or three fatty acid molecules, which canbe of varying lengths and have varying degrees of saturation. The lengthand saturation characteristics of the fatty acid molecules (and themicroalgal oils) can be manipulated to modify the properties orproportions of the fatty acid molecules in microalgal oils ofembodiments of the present invention via culture conditions or via lipidpathway engineering, as described in more detail in Section IV, below.Particular modifications of properties and proportions includealteration of the fatty acid distribution of the microbial triglyceridessuch as changes in chain length profile, saturation profile, andhydroxylation of fatty acids. The oils so produced can comprise anatural oil. Alternately, specific blends of microbial oil can beprepared either within a single species of algae by mixing together thebiomass or algal oil from two or more species of microalgae, or byblending algal oil of the invention with oils from other sources such assoy, rapeseed, canola, palm, palm kernel, coconut, corn, wastevegetable, Chinese tallow, olive, sunflower, cottonseed, chicken fat,beef tallow, porcine tallow, microalgae, macroalgae, microbes, Cuphea,flax, peanut, choice white grease, lard, Camelina sativa, mustard seed,cashew nut, oats, lupine, kenaf, calendula, help, coffee, linseed(flax), hazelnut, euphorbia, pumpkin seed, coriander, camellia, sesame,safflower, rice, tung tree, cocoa, copra, pium poppy, castor beans,pecan, jojoba, macadamia, Brazil nuts, avocado, petroleum, or adistillate fraction of any of the preceding oils.

The oil composition, i.e., the properties and proportions of the fattyacid constituents of the glycerolipids, can also be manipulated bycombining biomass or oil from at least two distinct species ofmicroorganism. In some embodiments, at least two of the distinct speciesof microalgae have different glycerolipid profiles. The distinct speciesof microalgae can be cultured together or separately as describedherein, preferably under heterotrophic conditions, to generate therespective oils. Different species of microalgae can contain differentpercentages of distinct fatty acid constituents in the cell'sglycerolipids.

Generally, Prototheca strains have very little or no fatty acids withthe chain length C8-C14. For example, Prototheca moriformis (UTEX 1435),Prototheca krugani (UTEX 329), Prototheca stagnora (UTEX 1442) andPrototheca zopfii (UTEX 1438) contains no (or undectable amounts) C8fatty acids, between 0-0.01% C10 fatty acids, between 0.03-2.1% C12fatty acids and between 1.0-1.7% C14 fatty acids.

In some cases, the microbial strains containing a transgene encoding afatty acyl-ACP thioesterase that has activity towards fatty acyl-ACPsubstrate of chain lengths C8 or C8-10 has at least 1.5%, at least 3.0%,at least 10%, at least 12% or more fatty acids of chain length C8. Inother instances, the microbial strains containing a transgene encoding afatty acyl ACP thioesterase that has activity towards fatty acyl-ACPsubstrate of chain lengths C10 has at least at least 5.0%, at least10.0%, at least 24%, at least 29% or more fatty acids of chain lengthC10. In other instances, the microbial strains containing a transgeneencoding a fatty acyl-ACP thioesterase that has activity towards fattyacyl-ACP substrate of chain length C12 has at least 5%, at least 15%, atleast 34%, at least 50% or more fatty acids of the chain length C12. Inother cases, the microbial strains containing a transgene encoding afatty acyl-ACP thioesterase that has activity towards fatty acyl-ACPsubstrate of chain length C14 has at least 2.0%, at least 7%, at least10%, at least 15%, at least 30%, at least 43% or more fatty acids of thechain length C14. In other cases, the microbial strains containing atransgene encoding a fatty acyl-ACP thioesterase that has activitytowards fatty acyl-ACP substrate of chain length C16 has at least 30%,at least 40%, at least 66% or more fatty acids of the chain length C16.In still other cases, the microbial strains containing a transgeneencoding a fatty acyl-ACP thioesterase that has activity towards fattyacyl-ACP substrate of chain length C18 and specifically for C18:0, hasat least 5%, at least 10%, at least 26%, at least 40% or more C18:0fatty acid levels. In any of these examples the microbe can be amicroalgae, such as Prototheca.

In non-limiting examples, a microbial strain containing a transgeneencoding a fatty acyl-ACP thioesterase that has activity towards fattyacyl-ACP substrate of chain length C8 has between 1-20%, preferablybetween 1.8-13%, fatty acids of chain length C8. In other non-limitingexamples, a microbial strain containing a transgene encoding a fattyacyl-ACP thioesterase that has activity towards fatty acyl-ACP substrateof chain length C10 has between 1-40%, preferably between 1.91-30%,fatty acids of chain length C10. In other non-limiting examples,microbial strains containing a transgene encoding a fatty acyl-ACPthioesterase that has activity towards fatty acyl-ACP substrate of chainlength C12 has between 10-60%, preferably between 13.55-55%, fatty acidsof the chain length C12. In other non-limiting examples, microbialstrains containing a transgene encoding a fatty acyl-ACP thioesterasethat has activity towards fatty acyl-ACP substrate of chain length C14has between 1-50%, preferably between 2.59-43.27%, fatty acids of thechain length C14. In other non-limiting examples, microbial strainscontaining a transgene encoding a fatty acyl-ACP thioesterase that hasbroad specificity towards fatty acyl-ACP substrates of varying carbonchain length has up to 70% fatty acids of the chain length C16. In othercases, microbial strains containing a transgene encoding a fattyacyl-ACP thioesterase that has activity towards fatty acyl-ACP substrateof chain length C16 has up to 75%, preferably up to 67.42%, fatty acidsof the chain length C16. In some cases, the microbial strains containinga transgene encoding a fatty acyl-ACP thioesterase that has activitytowards fatty acyl-ACP substrate of chain lengths between C8 and C14have between 1-790%, or between about 2-80%, (C8-C14) fatty acids. Insome cases, the microbial strains containing a transgene encoding afatty acyl-ACP thioesterase that has activity towards fatty acyl-ACPsubstrates of chain lengths between C12 and C14 have at least 50% or60%, C12-C14 fatty acids. In some instances, keeping the transgenicmicrobial strains under constant and high selective pressure to retainexogenous genes is advantageous due to the increase in the desired fattyacid of a specific chain length. High levels of exogenous gene retentioncan also be achieved by inserting exogenous genes into the nuclearchromosomes of the cells using homologous recombination vectors andmethods disclosed herein. Recombinant cells containing exogenous genesintegrated into nuclear chromosomes are an object of the invention. Inany of these examples the microbe can be a microalgae, such asPrototheca.

Optionally, the microbial oil can also include other constituentsproduced by the microalgae, or incorporated into the microalgal oil fromthe culture medium. These other constituents can be present in varyingamount depending on the culture conditions used to culture themicroalgae, the species of microalgae, the extraction method used torecover microalgal oil from the biomass and other factors that mayaffect microalgal oil composition. Non-limiting examples of suchconstituents include carotenoids, present from 0.025-0.3 mcg/g,preferably from 0.05 to 0.244 micrograms/gram, of oil; chlorophyll Apresent from 0.025-0.3 mcg/g, preferably from 0.045 to 0.268micrograms/gram, of oil; total chlorophyll of less than 0.03 mcg/g,preferably less than 0.025 micrograms/gram, of oil; gamma tocopherolpresent from 35-175 mcg/g, preferably from 38.3-164 micrograms/gram, ofoil; total tocopherols present from 50-300 mcg/g, preferably from 60.8to 261.7 microgram/gram, of oil; less than 0.5%, preferably less than0.25%, brassicasterol, campesterol, stigmasterol, or betasitosterol;total tocotrienols less than 300 micrograms/gram of oil; and totaltocotrienols present from 225-350 mcg/g, preferably from 249.6 to 325.3micrograms/gram, of oil.

The other constituents can include, without limitation, phospholipids,tocopherols, tocotrienols, carotenoids (e.g., alpha-carotene,beta-carotene, lycopene, etc.), xanthophylls (e.g., lutein, zeaxanthin,alpha-cryptoxanthin and beta-crytoxanthin), and various organic orinorganic compounds. In some cases, the oil extracted from Protothecaspecies comprises between 0.001 to 0.05, preferably from 0.003 to 0.039,microgram lutein/gram of oil, less than 0.005, preferably less than0.003, micrograms lycopene/gram of oil; and less than 0.005, preferablyless than 0.003, microgram beta carotene/gram of oil.

III. GENETIC ENGINEERING METHODS AND MATERIALS

The present invention provides methods and materials for geneticallymodifying Prototheca cells and recombinant host cells useful in themethods of the present invention, including but not limited torecombinant Prototheca moriformis, Prototheca zopfii, Protothecakrugani, and Prototheca stagnora host cells. The description of thesemethods and materials is divided into subsections for the convenience ofthe reader. In subsection 1, transformation methods are described. Insubsection 2, genetic engineering methods using homologous recombinationare described. In subsection 3, expression vectors and components aredescribed.

1. Engineering Methods—Transformation

Cells can be transformed by any suitable technique including, e.g.,biolistics, electroporation (see Maruyama et al. (2004), BiotechnologyTechniques 8:821-826), glass bead transformation and silicon carbidewhisker transformation. Another method that can be used involves formingprotoplasts and using CaCl₂ and polyethylene glycol (PEG) to introducerecombinant DNA into microalgal cells (see Kim et al. (2002), Mar.Biotechnol. 4:63-73, which reports the use of this method for thetransformation of Chorella ellipsoidea). Co-transformation of microalgaecan be used to introduce two distinct vector molecules into a cellsimultaneously (see for example Protist 2004 December; 155(4):381-93).

Biolistic methods (see, for example, Sanford, Trends In Biotech. (1988)6:299 302, U.S. Pat. No. 4,945,050; electroporation (Fromm et al., Proc.Nat'l. Acad. Sci. (USA) (1985) 82:5824 5828); use of a laser beam,microinjection or any other method capable of introducing DNA into amicroalgae can also be used for transformation of a Prototheca cell.

2. Engineering Methods—Homologous Recombination

Homologous recombination is the ability of complementary DNA sequencesto align and exchange regions of homology. Transgenic DNA (“donor”)containing sequences homologous to the genomic sequences being targeted(“template”) is introduced into the organism and then undergoesrecombination into the genome at the site of the corresponding genomichomologous sequences.

The ability to carry out homologous recombination in a host organism hasmany practical implications for what can be carried out at the moleculargenetic level and is useful in the generation of an oleaginous microbethat can produced tailored oils. By its very nature homologousrecombination is a precise gene targeting event, hence, most transgeniclines generated with the same targeting sequence will be essentiallyidentical in terms of phenotype, necessitating the screening of farfewer transformation events. Homologous recombination also targets geneinsertion events into the host chromosome, potentially resulting inexcellent genetic stability, even in the absence of genetic selection.Because different chromosomal loci will likey impact gene expression,even from heterologous promoters/UTRs, homologous recombination can be amethod of querying loci in an unfamiliar genome environment and toassess the impact of these environments on gene expression.

A particularly useful genetic engineering approach using homologousrecombination is to co-opt specific host regulatory elements such aspromoters/UTRs to drive heterologous gene expression in a highlyspecific fashion. For example, ablation or knockout of desaturasegenes/gene families with a heterologous gene encoding a selective markermight be expected to increase the overall percentage of saturated fattyacids produced in the host cell. Example 6 describes the homologousrecombination targeting constructs and a working example of suchdesaturase gene ablations or knockouts generated in Protothecamoriformis. Another approach to decreasing expression of an endogenousgene is to use an RNA-induced downregulation or silencing of geneexpression including, but not limited to an RNAi or antisense approach,as well as a dsRNA approach. Antisense, RNAi, dsRNA approaches are wellknown in the art and include the introduction of an expression constructthat when expressed as mRNA would lead to the formation of hairpin RNAor an expression construct containing a portion of the target gene thatwould be transcribed in the antisense orientation. All three approacheswould result in the decreased expression of the target gene. Example 6also describes expression constructs and a working example of thedown-regulation of an endogenous Prototheca moriformis delta 12desaturase gene (FADc) by an RNAi and antisense approach.

Because homologous recombination is a precise gene targeting event, itcan be used to precisely modify any nucleotide(s) within a gene orregion of interest, so long as sufficient flanking regions have beenidentified. Therefore, homologous recombination can be used as a meansto modify regulatory sequences impacting gene expression of RNA and/orproteins. It can also be used to modify protein coding regions in aneffort to modify enzyme activities such as substrate specificity,affinities and Km, and thus affecting the desired change in metabolismof the host cell. Homologous recombination provides a powerful means tomanipulate the host genome resulting in gene targeting, gene conversion,gene deletion, gene duplication, gene inversion and exchanging geneexpression regulatory elements such as promoters, enhancers and 3′UTRs.

Homologous recombination can be achieve by using targeting constructscontaining pieces of endogenous sequences to “target” the gene or regionof interest within the endogenous host cell genome. Such targetingsequences can either be located 5′ of the gene or region of interest, 3′of the gene/region of interest or even flank the gene/region ofinterest. Such targeting constructs can be transformed into the hostcell either as a supercoiled plasmid DNA with additional vectorbackbone, a PCR product with no vector backbone, or as a linearizedmolecule. In some cases, it may be advantageous to first expose thehomologous sequences within the transgenic DNA (donor DNA) with arestriction enzyme. This step can increase the recombination efficiencyand decrease the occurrence of undesired events. Other methods ofincreasing recombination efficiency include using PCR to generatetransforming transgenic DNA containing linear ends homologous to thegenomic sequences being targeted.

For purposes of non-limiting illustration, regions of donor DNAsequences that are useful for homologous recombination include the KE858region of DNA in Prototheca moriformis. KE858 is a 1.3 kb, genomicfragment that encompasses part of the coding region for a protein thatshares homology with the transfer RNA (tRNA) family of proteins.Southern blots have shown that the KE858 sequence is present in a singlecopy in the Prototheca moriformis (UTEX 1435) genome. This region andExamples of using this region for homologous recombination targeting hasbeen described in PCT Application No. PCT/US2009/066142. Another regionof donor DNA that is useful is the genomic sequence denoted here as “6S”(donor sequences at SEQ ID NO: 82, SEQ ID NO: 84). Note that the 6Ssequence is not the 6S rRNA sequence. The use of this sequence inhomologous recombination in Prototheca moriformis are described below inthe Examples.

3. Vectors and Vector Components

Vectors for transformation of microorganisms in accordance with thepresent invention can be prepared by known techniques familiar to thoseskilled in the art in view of the disclosure herein. A vector typicallycontains one or more genes, in which each gene codes for the expressionof a desired product (the gene product) and is operably linked to one ormore control sequences that regulate gene expression or target the geneproduct to a particular location in the recombinant cell. To aid thereader, this subsection is divided into subsections. Subsection Adescribes control sequences typically contained on vectors as well asnovel control sequences provided by the present invention. Subsection Bdescribes genes typically contained in vectors as well as novel codonoptimization methods and genes prepared using them provided by theinvention.

A. Control Sequences

Control sequences are nucleic acids that regulate the expression of acoding sequence or direct a gene product to a particular location in oroutside a cell. Control sequences that regulate expression include, forexample, promoters that regulate transcription of a coding sequence andterminators that terminate transcription of a coding sequence. Anothercontrol sequence is a 3′ untranslated sequence located at the end of acoding sequence that encodes a polyadenylation signal. Control sequencesthat direct gene products to particular locations include those thatencode signal peptides, which direct the protein to which they areattached to a particular location in or outside the cell.

Thus, an exemplary vector design for expression of an exogenous gene ina microalgae contains a coding sequence for a desired gene product (forexample, a selectable marker, a lipid pathway modification enzyme, or asucrose utilization enzyme) in operable linkage with a promoter activein microalgae. Alternatively, if the vector does not contain a promoterin operable linkage with the coding sequence of interest, the codingsequence can be transformed into the cells such that it becomes operablylinked to an endogenous promoter at the point of vector integration. Thepromoterless method of transformation has been proven to work inmicroalgae (see for example Plant Journal 14:4, (1998), pp. 441-447).

Many promoters are active in microalgae, including promoters that areendogenous to the algae being transformed, as well as promoters that arenot endogenous to the algae being transformed (i.e., promoters fromother algae, promoters from higher plants, and promoters from certainplant viruses or algae viruses). Illustrative exogenous and/orendogenous promoters that are active in microalgae (as well asantibiotic resistance genes functional in microalgae) are described inPCT Pub. No. 2008/151149 and references cited therein).

The promoter used to express an exogenous gene can be the promoternaturally linked to that gene or can be a heterologous promoter. Somepromoters are active in more than one species of microalgae. Otherpromoters are species-specific. Illustrative promoters include promoterssuch as β-tubulin from Chlamydomonas reinhardtii, used in the Examplesbelow, and viral promoters, such as cauliflower mosaic virus (CMV) andchlorella virus, which have been shown to be active in multiple speciesof microalgae (see for example Plant Cell Rep. 2005 March;23(10-11):727-35; J Microbiol. 2005 August; 43(4):361-5; Mar Biotechnol(NY). 2002 January; 4(1):63-73). Another promoter that is suitable foruse for expression of exogenous genes in Prototheca is the Chlorellasorokiniana glutamate dehydrogenase promoter/5′UTR. Optionally, at least10, 20, 30, 40, 50, or 60 nucleotides or more of these sequencescontaining a promoter are used. Illustrative promoters useful forexpression of exogenous genes in Prototheca are listed in the sequencelisting of this application, such as the promoter of the Chlorella HUP1gene (SEQ ID NO: 1) and the Chlorella ellipsoidea nitrate reductasepromoter (SEQ ID NO:2). Chlorella virus promoters can also be used toexpress genes in Prototheca, such as SEQ ID NOs: 1-7 of U.S. Pat. No.6,395,965. Additional promoters active in Prototheca can be found, forexample, in Biochem Biophys Res Commun. 1994 Oct. 14; 204(1):187-94;Plant Mol Biol. 1994 October; 26(1):85-93; Virology. 2004 Aug. 15;326(1):150-9; and Virology. 2004 Jan. 5; 318(1):214-23. Other usefulpromoters are described in detail in the Examples below.

A promoter can generally be characterized as either constitutive orinducible. Constitutive promoters are generally active or function todrive expression at all times (or at certain times in the cell lifecycle) at the same level. Inducible promoters, conversely, are active(or rendered inactive) or are significantly up- or down-regulated onlyin response to a stimulus. Both types of promoters find application inthe methods of the invention. Inducible promoters useful in theinvention include those that mediate transcription of an operably linkedgene in response to a stimulus, such as an exogenously provided smallmolecule (e.g, glucose, as in SEQ ID NO:1), temperature (heat or cold),lack of nitrogen in culture media, etc. Suitable promoters can activatetranscription of an essentially silent gene or upregulate, preferablysubstantially, transcription of an operably linked gene that istranscribed at a low level. Examples below describe additional induciblepromoters that are useful in Prototheca cells.

Inclusion of termination region control sequence is optional, and ifemployed, then the choice is be primarily one of convenience, as thetermination region is relatively interchangeable. The termination regionmay be native to the transcriptional initiation region (the promoter),may be native to the DNA sequence of interest, or may be obtainable fromanother source. See, for example, Chen and Orozco, Nucleic Acids Res.(1988) 16:8411.

The present invention also provides control sequences and recombinantgenes and vectors containing them that provide for the directing a geneproduct of interest to a particular cell compartment such aschloroplasts, plastids, mitochondria, or endoplasmic reticulum. Inaddition, embodiments of the present invention include control sequencesand recombinant genes and vectors containing them that provide for thesecretion of a protein outside the cell.

Proteins expressed in the nuclear genome of Prototheca can be targetedto the plastid using plastid targeting signals. Plastid targetingsequences endogenous to Chlorella are known, such as genes in theChlorella nuclear genome that encode proteins that are targeted to theplastid; see for example GenBank Accession numbers AY646197 andAF499684, and in one embodiment, such control sequences are used in thevectors of the present invention to target expression of a protein to aPrototheca plastid.

The Examples below describe the use of algal plastid targeting sequencesto target heterologous proteins to the correct compartment in the hostcell. cDNA libraries were made using Prototheca moriformis and Chlorellaprotothecodies cells and are described in PCT Application No.PCT/US2009/066142.

In another embodiment of the present invention, the expression of apolypeptide in Prototheca is targeted to the endoplasmic reticulum. Theinclusion of an appropriate retention or sorting signal in an expressionvector ensure that proteins are retained in the endoplasmic reticulum(ER) and do not go downstream into Golgi. For example, theIMPACTVECTOR1.3 vector, from Wageningen UR-Plant Research International,includes the well known KDEL retention or sorting signal. With thisvector, ER retention has a practical advantage in that it has beenreported to improve expression levels 5-fold or more. The main reasonfor this appears to be that the ER contains lower concentrations and/ordifferent proteases responsible for post-translational degradation ofexpressed proteins than are present in the cytoplasm. ER retentionsignals functional in green microalgae are known. For example, see ProcNatl Acad Sci USA. 2005 Apr. 26; 102(17):6225-30.

In another embodiment of the present invention, a polypeptide istargeted for secretion outside the cell into the culture media. SeeHawkins et al., Current Microbiology Vol. 38 (1999), pp. 335-341 forexamples of secretion signals active in Chlorella that can be used, inaccordance with the methods of the invention, in Prototheca.

B. Genes and Codon Optimization

Typically, a gene includes a promoter, coding sequence, and terminationcontrol sequences. When assembled by recombinant DNA technology, a genemay be termed an expression cassette and may be flanked by restrictionsites for convenient insertion into a vector that is used to introducethe recombinant gene into a host cell. The expression cassette can beflanked by DNA sequences from the genome or other nucleic acid target tofacilitate stable integration of the expression cassette into the genomeby homologous recombination. Alternatively, the vector and itsexpression cassette may remain unintegrated (e.g., an episome), in whichcase, the vector typically includes an origin of replication, which iscapable of providing for replication of the heterologous vector DNA.

A common gene present on a vector is a gene that codes for a protein,the expression of which allows the recombinant cell containing theprotein to be differentiated from cells that do not express the protein.Such a gene, and its corresponding gene product, is called a selectablemarker or selection marker. Any of a wide variety of selectable markerscan be employed in a transgene construct useful for transformingPrototheca. Examples of suitable selectable markers include the G418resistance gene, the nitrate reductase gene (see Dawson et al. (1997),Current Microbiology 35:356-362), the hygromycin phosphotransferase gene(HPT; see Kim et al. (2002), Mar. Biotechnol. 4:63-73), the neomycinphosphotransferase gene, and the ble gene, which confers resistance tophleomycin (Huang et al. (2007), Appl. Microbiol. Biotechnol.72:197-205). Methods of determining sensitivity of microalgae toantibiotics are well known. For example, Mol Gen Genet. 1996 Oct. 16;252(5):572-9, sucrose invertase, as described herein, and thiamineauxotrophy complementation, as also described herein.

Other selectable markers that are not antibiotic-based can alsobeemployed in a transgene construct useful for transforming microalgae ingeneral, including Prototheca species. Genes that confers the ability toutilize certain carbon sources that were previously unable to beutilized by the microalgae can also be used as a selectable marker. Byway of illustration, Prototheca moriformis strains typically growpoorly, if at all, on sucrose. Using a construct containing a sucroseinvertase gene can confer the ability of positive transformants to growon sucrose as a carbon substrate. Additional details on using sucroseutilization as a selectable marker along with other selectable markersare discussed in Section IV below.

For purposes of the present invention, the expression vector used toprepare a recombinant host cell of the invention will include at leasttwo, and often three, genes, if one of the genes is a selectable marker.For example, a genetically engineered Prototheca of the invention can bemade by transformation with vectors of the invention that comprise, inaddition to a selectable marker, one or more exogenous genes, such as,for example, sucrose invertase gene or acyl ACP-thioesterase gene. Oneor both genes can be expressed using an inducible promoter, which allowsthe relative timing of expression of these genes to be controlled toenhance the lipid yield and conversion to fatty acid esters. Expressionof the two or more exogenous genes may be under control of the sameinducible promoter or under control of different inducible (orconstitutive) promoters. In the latter situation, expression of a firstexogenous gene can be induced for a first period of time (during whichexpression of a second exogenous gene may or may not be induced) andexpression of a second exogenous gene can be induced for a second periodof time (during which expression of a first exogenous gene may or maynot be induced).

In other embodiments, the two or more exogenous genes (in addition toany selectable marker) are: a fatty acyl-ACP thioesterase and a fattyacyl-CoA/aldehyde reductase, the combined action of which yields analcohol product. Further provided are other combinations of exogenousgenes, including without limitation, a fatty acyl-ACP thioesterase and afatty acyl-CoA reductase to generate aldehydes. In one embodiment, thevector provides for the combination of a fatty acyl-ACP thioesterase, afatty acyl-CoA reductase, and a fatty aldehyde decarbonylase to generatealkanes. In each of these embodiments, one or more of the exogenousgenes can be expressed using an inducible promoter.

Other illustrative vectors of the invention that express two or moreexogenous genes include those encoding both a sucrose transporter and asucrose invertase enzyme and those encoding both a selectable marker anda secreted sucrose invertase. The recombinant Prototheca transformedwith either type of vector produce lipids at lower manufacturing costdue to the engineered ability to use sugar cane (and sugar cane-derivedsugars) as a carbon source. Insertion of the two exogenous genesdescribed above can be combined with the disruption of polysaccharidebiosynthesis through directed and/or random mutagenesis, which steersever greater carbon flux into lipid production. Individually and incombination, trophic conversion, engineering to alter lipid productionand treatment with exogenous enzymes alter the lipid compositionproduced by a microorganism. The alteration can be a change in theamount of lipids produced, the amount of one or more hydrocarbon speciesproduced relative to other lipids, and/or the types of lipid speciesproduced in the microorganism. For example, microalgae can be engineeredto produce a higher amount and/or percentage of TAGs(triacylglycerides).

For optimal expression of a recombinant protein, it is beneficial toemploy coding sequences that produce mRNA with codons preferentiallyused by the host cell to be transformed. Thus, proper expression oftransgenes can require that the codon usage of the transgene matches thespecific codon bias of the organism in which the transgene is beingexpressed. The precise mechanisms underlying this effect are many, butinclude the proper balancing of available aminoacylated tRNA pools withproteins being synthesized in the cell, coupled with more efficienttranslation of the transgenic messenger RNA (mRNA) when this need ismet. When codon usage in the transgene is not optimized, available tRNApools are not sufficient to allow for efficient translation of theheterologous mRNA resulting in ribosomal stalling and termination andpossible instability of the transgenic mRNA.

The present invention provides codon-optimized nucleic acids useful forthe successful expression of recombinant proteins in Prototheca. Codonusage in Prototheca species was analyzed by studying cDNA sequencesisolated from Prototheca moriformis. This analysis represents theinterrogation over 24,000 codons and resulted in Table 2 below.

TABLE 2 Preferred codon usage in Prototheca strains. Ala GCG 345 (0.36)Asn AAT 8 (0.04) GCA 66 (0.07) AAC 201 (0.96) GCT 101 (0.11) Pro CCG 161(0.29) GCC 442 (0.46) CCA 49 (0.09) Cys TGT 12 (0.10) CCT 71 (0.13) TGC105 (0.90) CCC 267 (0.49) Asp GAT 43 (0.12) Gln CAG 226 (0.82) GAC 316(0.88) CAA 48 (0.18) Glu GAG 377 (0.96) Arg AGG 33 (0.06) GAA 14 (0.04)AGA 14 (0.02) Phe TTT 89 (0.29) CGG 102 (0.18) TTC 216 (0.71) CGA 49(0.08) Gly GGG 92 (0.12) CGT 51 (0.09) GGA 56 (0.07) CGC 331 (0.57) GGT76 (0.10) Ser AGT 16 (0.03) GGC 559 (0.71) AGC 123 (0.22) His CAT 42(0.21) TCG 152 (0.28) CAC 154 (0.79) TCA 31 (0.06) Ile ATA 4 (0.01) TCT55 (0.10) ATT 30 (0.08) TCC 173 (0.31) ATC 338 (0.91) Thr ACG 184 (0.38)Lys AAG 284 (0.98) ACA 24 (0.05) AAA 7 (0.02) ACT 21 (0.05) Leu TTG 26(0.04) ACC 249 (0.52) TTA 3 (0.00) Val GTG 308 (0.50) CTG 447 (0.61) GTA9 (0.01) CTA 20 (0.03) GTT 35 (0.06) CTT 45 (0.06) GTC 262 (0.43) CTC190 (0.26) Trp TGG 107 (1.00) Met ATG 191 (1.00) Tyr TAT 10 (0.05) TAC180 (0.95) Stop TGA/TAG/TAA

In other embodiments, the gene in the recombinant vector has beencodon-optimized with reference to a microalgal strain other than aPrototheca strain. For example, methods of recoding genes for expressionin microalgae are described in U.S. Pat. No. 7,135,290. Additionalinformation for codon optimization is available, e.g., at the codonusage database of GenBank.

In connection with embodiments having codon optimized genes, theoptimized genes are preferably optimized so as to increase expression ofthe gene product of the gene being optimized by at least 10% and morepreferably by at least 20, 40, 60, 80, 100, or 200%.

While the methods and materials of the invention allow for theintroduction of any exogenous gene into Prototheca, genes relating tosucrose utilization and lipid pathway modification are of particularinterest, as discussed in the following sections.

IV. SELECTABLE MARKERS

1. Sucrose Utilization

In an embodiment, the recombinant cell of the invention further containsone or more exogenous sucrose utilization genes. In various embodiments,the one or more genes encode one or more proteins selected from thegroup consisting of a fructokinase, a glucokinase, a hexokinase, asucrose invertase, a sucrose transporter. For example, expression of asucrose transporter and a sucrose invertase allows Prototheca totransport sucrose into the cell from the culture media and hydrolyzesucrose to yield glucose and fructose. Optionally, a fructokinase can beexpressed as well in instances where endogenous hexokinase activity isinsufficient for maximum phosphorylation of fructose. Examples ofsuitable sucrose transporters are Genbank accession numbers CAD91334,CAB92307, and CAA53390. Examples of suitable fructokinases are Genbankaccession numbers P26984, P26420 and CAA43322.

In one embodiment, the present invention provides a host cell thatsecretes a sucrose invertase. Secretion of a sucrose invertase obviatesthe need for expression of a transporter that can transport sucrose intothe cell. This is because a secreted invertase catalyzes the conversionof a molecule of sucrose into a molecule of glucose and a molecule offructose, both of which can be transported and utilized by microbesprovided by the invention. For example, expression of a sucroseinvertase (such as SEQ ID NO:3) with a secretion signal (such as that ofSEQ ID NO: 4 (from yeast), SEQ ID NO: 5 (from higher plants), SEQ ID NO:6 (eukaryotic consensus secretion signal), and SEQ ID NO: 7 (combinationof signal sequence from higher plants and eukaryotic consensus)generates invertase activity outside the cell. Expression of such aprotein, as enabled by the genetic engineering methodology disclosedherein, allows cells already capable of utilizing extracellular glucoseas an energy source to utilize sucrose as an extracellular energysource.

Prototheca species expressing an invertase in media containing sucroseare a preferred microalgal species for the production of oil. Theexpression and extracellular targeting of this fully active proteinallows the resulting host cells to grow on sucrose, whereas theirnon-transformed counterparts cannot. Thus, embodiments of the presentinvention provide recombinant microalgae (including Prototheca) cellswith a codon-optimized invertase gene, including but not limited to theyeast invertase gene, integrated into their genome such that theinvertase gene is expressed as assessed by invertase activity andsucrose hydrolysis. Invertase genes are useful as selectable markers inthe recombinant cells, as such cells are able to grow on sucrose, whiletheir non-transformed counterparts cannot; and methods for selectingrecombinant host cells using an invertase as a powerful, selectablemarker for algal molecular genetics.

The successful expression of a sucrose invertase in Prototheca alsoillustrates another aspect of the present invention in that itdemonstrates that heterologous (recombinant) proteins can be expressedin the algal cell and successfully transit outside of the cell and intothe culture medium in a fully active and functional form. Thus,embodiments of the present invention provide methods and reagents forexpressing a wide and diverse array of heterologous proteins inmicroalgae and secreting them outside of the host cell. Such proteinsinclude, for example, industrial enzymes such as, for example, lipases,proteases, cellulases, pectinases, amylases, esterases, oxidoreductases,transferases, lactases, isomerases, and invertases, as well astherapeutic proteins such as, for example, growth factors, cytokines,full length antibodies comprising two light and two heavy chains, Fabs,scFvs (single chain variable fragment), camellid-type antibodies,antibody fragments, antibody fragment-fusions, antibody-receptorfusions, insulin, interferons, and insulin-like growth factors.

The successful expression of a sucrose invertase in Prototheca alsoillustrates another aspect of the present invention in that it providesmethods and reagents for the use of fungal transit peptides in algae todirect secretion of proteins in Prototheca; and methods and reagents fordetermining if a peptide can function, and the ability of it tofunction, as a transit peptide in Prototheca cells. The methods andreagents of the invention can be used as a tool and platform to identifyother transit peptides that can successfully traffic proteins outside ofa cell, and that the yeast invertase has great utility in these methods.As demonstrated in this example, removal of the endogenous yeastinvertase transit peptide and its replacement by other transit peptides,either endogenous to the host algae or from other sources (eukaryotic,prokaryotic and viral), can identify whether any peptide of interest canfunction as a transit peptide in guiding protein egress from the cell.

Examples of suitable sucrose invertases include those identified byGenbank accession numbers CAB95010, NP_012104 and CAA06839. Non-limitingexamples of suitable invertases are listed below in Table 3. Amino acidsequences for each listed invertase are included in the Sequence Listingbelow. In some cases, the exogenous sucrose utilization gene suitablefor use in the methods and vectors of the invention encodes a sucroseinvertase that has at least 40, 50, 60, 75, or 90% or higher amino acididentity with a sucrose invertase selected from Table 3.

TABLE 3 Sucrose invertases. GenBank Description Organism Accession No.SEQ ID NO: Invertase Chicorium intybus Y11124 SEQ ID NO: 20 InvertaseSchizosaccharomyces AB011433 SEQ ID NO: 21 pombe beta- Pichia anomalaX80640 SEQ ID NO: 22 fructo- furanosidase (invertase) InvertaseDebaryomyces X17604 SEQ ID NO: 23 occidentalis Invertase Oryza sativaAF019113 SEQ ID NO: 24 Invertase Allium cepa AJ006067 SEQ ID NO: 25Invertase Beta vulgaris subsp. AJ278531 SEQ ID NO: 26 Vulgaris beta-Bifidobacterium breve AAT28190 SEQ ID NO: 27 fructo- UCC2003furanosidase (invertase) Invertase Saccharomyces NP_012104 SEQ ID NO: 8cerevisiae (nucleotide) SEQ ID NO: 28 (amino acid) Invertase A Zymomonasmobilis AAO38865 SEQ ID NO: 29

The secretion of an invertase to the culture medium by Prototheca enablethe cells to grow as well on waste molasses from sugar cane processingas they do on pure reagent-grade glucose; the use of this low-valuewaste product of sugar cane processing can provide significant costsavings in the production of lipids and other oils. Thus, the presentinvention provides a microbial culture containing a population ofPrototheca microorganisms, and a culture medium comprising (i) sucroseand (ii) a sucrose invertase enzyme. In various embodiments the sucrosein the culture comes from sorghum, sugar beet, sugar cane, molasses, ordepolymerized cellulosic material (which may optionally contain lignin).In another aspect, the methods and reagents of the inventionsignificantly increase the number and type of feedstocks that can beutilized by recombinant microalgae or other microbes. While the microbesexemplified here are altered such that they can utilize sucrose, themethods and reagents of the invention can be applied so that feedstockssuch as cellulosics are utilizable by an engineered host microbe of theinvention with the ability to secrete cellulases, pectinases,isomerases, or the like, such that the breakdown products of theenzymatic reactions are no longer just simply tolerated but ratherutilized as a carbon source by the host. An example of this is describedbelow and in the Examples of microbes engineered to express a secretableα-galactosidase, conferring the ability to hydrolyze α-galactosyl bondsin oligosaccharides such as those contained in raffinose and stachyosewhich are two oligosaccharides found in agricultural waste streams.

2. Alpha-Galactosidase Expression

While the expression of a sucrose invertase, as described above, confersthe ability for Prototheca cells to more efficiently utilize sucrose asa carbon source (via the enzyme hydrolyzing the α-linkage betweenfructose and glucose molecules in the disaccharide sucrose), theexpression of other enzymes that hydrolyze other types of α-linkages inoligosaccharides can confer the ability for Prototheca cells to utilizeother carbon sources. The expression of these enzymes (and the resultingability to utilize carbon sources that Prototheca and other microalgalcells ordinarily would not be able to) can be used as a selectablemarker for these transgenic Prototheca cells by allowing for theselection of positive clones that are able to grow on these carbonsources.

In an embodiment, the recombinant Prototheca cell of the inventionfurther contains one or more exogenous genes encodingpolysaccharide-degrading enzymes. In various embodiments, the one ormore genes encoding a polysaccharide-degrading enzyme is a gene encodinga secreted α-galactosidase. The expression of an exogenous secretedα-galactosidase in a Prototheca cell confers the ability of suchtransformed strains to grow on sugars (carbon sources) containingD-galactosyl linkages, such as α-linkages between galactose and glucosemonosaccharide units. Prototheca strains expressing an exogenous,secreted α-galactosidase will be able to utilize disaccharides such asmelibiose (disaccharide composed of α-D-galactose-glucose).

Sugars such as raffinose (a trisaccharide comprised of α-linkedgalactose-glucose-fructose) and stachyose (a tetrasaccharide composed totwo α-linked D-galactose units, followed by α-linked glucose andfructose) are present in significant proportions in agricultural wastestreams such as beet pulp (raffinose) and soybean meal (stachyose). Suchagricultural residues represent a significant untapped carbon source forthe conversion into oil by microbes (including Prototheca) capable ofutilizing them.

Prototheca strains are unable to utilize oligosaccharides such asraffinose and stachyose in any significant quantity or at all. In thecase of raffinose and stachyose, although transgenic strains expressinga sucrose invertase (as described above) have the ability to hydrolyzethe α-linkage between fructose and glucose in α-galactosyl derivativesof sucrose, but the remainder of the oligosaccharide remains unutilized,as sucrose invertase will not cleave the remaining α-linkages in suchsugars and the resulting disaccharides are not utilizable. In anotherembodiment, the recombinant Prototheca cell of the invention comprisesboth an exogenous gene encoding a sucrose invertase and an exogenousgene encoding an α-galactosidase. Thus, strains expressing both asucrose invertase and an α-galactosidase will be capable of fullyhydrolyzing oligosaccharides such as raffinose and stachyose, enablingthe consumption of the component monomers. In addition, α-galactosidaseencoding genes may be used as a selectable marker for transformation.Clones containing the exogenous α-galactosidase gene will have theability to grow on melibiose. Examples of suitable α-galactosidase genesfor use in Prototheca strains include the MEL1 gene from Saccharomycescarlbergensis, the AglC gene from Aspergillus niger. Interestingly, notall α-galactosidase genes have been found to be functional in Protothecaspecies, even if the genes are optimized according to the preferredcodon usage in Prototheca strains. The Examples below demonstrates theability of transgenic Prototheca cells to grow on melibiose whentransformed with codon-optimized MEL1 gene from S. carlbergensis and theAglC gene from A. niger, but not an α-galactosidase encoding gene fromthe higher plant, Cyamopsis tetragonobola (Guar bean).

3. Thiamine Auxotrophy Complementation

Prototheca strains including Prototheca moriformis are known to bethiamine auxotrophic (See, for example, Ciferri, O. (1956) Nature, v.178, pp. 1475-1476), meaning that these strains require thiamine in thenutrient media for growth. Thiamine auxotrophy can be the result ofmutations or lack of expression of enzymes in the thiamine biosyntheticpathway. Complemented transgenic strains expressing the missingenzyme(s) in the thiamine biosynthetic pathway can then be grown withoutadded thiamine, thus reducing the cost of the nutrient media as well asrendering the resulting microalgal biomass more desireable for use as ananimal feed. Complementation with a thiamine biosynthetic pathway enzymecan also be used as a selectable marker as the transgenic gene confersthe ability to grow on plates/media that does not contain thiamine.

In an embodiment, the recombinant Prototheca cell of the inventionfurther contains one or more exogenous genes encoding thiaminebiosynthetic pathway enzyme. In another embodiment, the recombinantPrototheca cell of the invention comprises an exogenous gene encodinghydroxymethylpyrimidine phosphate synthases from algal, plant orcyanobacterial sources. In still other embodiments, thehydroxymethylpyrimidine phosphate synthase is encoded by a THIC gene. Instill other embodiments, the THIC gene the Coccomyxa C-169 THIC,Arabidopsis thaliana THIC, or the Synechocystis sp. PCC 6803 thiC. TheExamples below details the engineering of Prototheca moriformis UTEX1435 with restored thiamine prototrophy.

V. LIPID PATHWAY ENGINEERING

In addition to altering the ability of microalgae or other microbes toutilize feedstocks such as sucrose-containing feedstocks, the presentinvention also provides recombinant microalgae or other microbes thathave been modified to alter the properties and/or proportions of lipidsproduced. The pathway can further, or alternatively, be modified toalter the properties and/or proportions of various lipid moleculesproduced through enzymatic processing of lipids and intermediates in thefatty acid pathway. In various embodiments, the recombinant Protothecacells of the invention have, relative to their untransformedcounterparts, optimized lipid yield per unit volume and/or per unittime, carbon chain length (e.g., for renewable diesel production or forindustrial chemicals applications requiring lipid feedstock), reduced orincreased number and/or position of double bonds, optionally to zero,hydroxylation of fatty acids, and increasing the hydrogen:carbon ratioof a particular species of lipid or of a population of distinct lipid.

In particular embodiments, one or more key enzymes that control branchpoints in metabolism to fatty acid synthesis have been up-regulated ordown-regulated to improve lipid production. Up-regulation can beachieved, for example, by transforming cells with expression constructsin which a gene encoding the enzyme of interest is expressed, e.g.,using a strong promoter and/or enhancer elements that increasetranscription. Such constructs can include a selectable marker such thatthe transformants can be subjected to selection, which can result ingene maintenance, and possibly amplification of the construct and anincrease in the expression level of the encoded enzyme. Examples ofenzymes suitable for up-regulation according to the methods of theinvention include pyruvate dehydrogenase, which plays a role inconverting pyruvate to acetyl-CoA (examples, some from microalgae,include Genbank accession numbers NP_415392; AAA53047; Q1XDM1; andCAF05587). Up-regulation of pyruvate dehydrogenase can increaseproduction of acetyl-CoA, and thereby increase fatty acid synthesis.Acetyl-CoA carboxylase catalyzes the initial step in fatty acidsynthesis. Accordingly, this enzyme can be up-regulated to increaseproduction of fatty acids (examples, some from microalgae, includeGenbank accession numbers BAA94752; AAA75528; AAA81471; YP_537052;YP_536879; NP_045833; and BAA57908). Fatty acid production can also beincreased by up-regulation of acyl carrier protein (ACP), which carriesthe growing acyl chains during fatty acid synthesis (examples, some frommicroalgae, include Genbank accession numbers A0T0F8; P51280; NP_849041;YP_874433). Glycerol-3-phosphate acyltransferase catalyzes therate-limiting step of fatty acid synthesis. Up-regulation of this enzymecan increase fatty acid production (examples, some from microalgae,include Genbank accession numbers AAA74319; AAA33122; AAA37647; P44857;and AB094442).

Up- and/or down-regulation of genes can be applied to global regulatorscontrolling the expression of the genes of the fatty acid biosyntheticpathways. Accordingly, one or more global regulators of fatty acidsynthesis can be up- or down-regulated, as appropriate, to inhibit orenhance, respectively, the expression of a plurality of fatty acidsynthetic genes and, ultimately, to increase lipid production. Examplesinclude sterol regulatory element binding proteins (SREBPs), such asSREBP-1a and SREBP-1c (for examples see Genbank accession numbersNP_035610 and Q9WTN3).

The present invention also provides recombinant Prototheca cells thathave been modified to contain one or more exogenous genes encoding lipidmodification enzymes such as, for example, fatty acyl-ACP thioesterases(see Table 4), fatty acyl-CoA/aldehyde reductases (see Table 6), fattyacyl-CoA reductases (see Table 7), fatty aldehyde decarbonylase (seeTable 8), fatty aldehyde reductases, desaturases (such as stearoyl-ACPdesaturases and fatty acyl desaturases and squalene synthases (seeGenBank Accession number AF205791). Although fatty acyl-ACPthioesterases typically do not directly chemically modify the lipids,their manipulation in accordance with embodiments of the invention canalter the fatty acid profile of a cell, especially in terms of chainlength and double bond distribution. In some embodiments, genes encodinga fatty acyl-ACP thioesterase and a naturally co-expressed acyl carrierprotein are transformed into a Prototheca or other microalgal ormicrobial cell, optionally with one or more genes encoding other lipidmodification enzymes. In other embodiments, the ACP and the fattyacyl-ACP thioesterase may have an affinity for one another that impartsan advantage when the two are used together in the microbes and methodsof the present invention, irrespective of whether they are or are notnaturally co-expressed in a particular tissue or organism. Thus,embodiments of the present invention contemplate both naturallyco-expressed pairs of these enzymes as well as those that share anaffinity for interacting with one another to facilitate cleavage of alength-specific carbon chain from the ACP.

In still other embodiments, an exogenous gene encoding a desaturase istransformed into the microalgal or other microbial cell in conjunctionwith one or more genes encoding other lipid modification enzymes toprovide modifications with respect to lipid saturation. In otherembodiments, an endogenous desaturase gene is overexpressed (e.g.,through the introduction of additional copies off the gene) in amicroalgal or other microbial cell. Stearoyl-ACP desaturase (see, e.g.,GenBank Accession numbers AAF15308; ABM45911; and AAY86086), forexample, catalyzes the conversion of stearoyl-ACP to oleoyl-ACP.Up-regulation of this gene can increase the proportion ofmonounsaturated fatty acids produced by a cell; whereas down-regulationcan reduce the proportion of monounsaturates. For illustrative purposes,stearoyl-ACP desaturases (SAD) are responsible for the synthesis ofC18:1 fatty acids from C18:0 precursors. Another family of desaturasesare the fatty acyl desaturases (FAD), including delta 12 fatty aciddesaturases (Δ12 FAD). These desaturases also provide modifications withrespect to lipid saturation. For illustrative purposes, delta 12 fattyacid desaturases are responsible for the synthesis of C18:2 fatty acidsfrom C18:1 precursors. Similarly, the expression of one or moreglycerolipid desaturases can be controlled to alter the ratio ofunsaturated to saturated fatty acids such as ω-6 fatty acid desaturase,ω-3 fatty acid desaturase, or ω-6-oleate desaturase. In someembodiments, the desaturase can be selected with reference to a desiredcarbon chain length, such that the desaturase is capable of makinglocation specific modifications within a specified carbon-lengthsubstrate, or substrates having a carbon-length within a specifiedrange. In another embodiment, if the desired fatty acid profile is anincrease in monounsaturates (such as C16:1 and/or C18:1) overexpressionof a SAD or expression of a heterologous SAD can be coupled with thesilencing or inactivation (e.g., through mutation, RNAi, antisense, orknockout of an endogenous desaturase gene, etc.) of a fatty acyldesaturase (FAD) or another desaturase gene.

In other embodiments, the microalgal or other microbial cell has beenmodified to have a mutated endogenous desaturase gene, wherein themutation renders the gene or desaturase enzyme inactive. In some cases,the mutated endogenous desaturase gene is a fatty acid desaturase (FAD).In other cases, the mutated endogenous desaturase gene is a stearoylAcyl carrier protein desaturase (SAD). Example 6 below describes thetargeted ablation or knockout of stearoyl-ACP desaturases and delta 12fatty acid desaturases in Prototheca. Example 6 also describes the useof RNAi or antisense constructs to decrease the expression of anendogenous desaturase gene.

In some cases, it may be advantageous to pair one or more of the geneticengineering techniques in order to achieve a trangenic cell thatproduces the desired lipid profile. In one embodiment, a microalgal orother microbial cell comprises a mutated endogenous desaturase gene andone or more exogenous gene. In non-limiting examples, a microalgal orother microbial cell with a mutated endogenous desaturase gene can alsoexpress an exogenous fatty acyl-ACP thioesterase gene and/or a sucroseinvertase gene. Example 6 below describes a transgenic Prototheca cellcontaining a targeted ablation or knockout of an endogenous SAD and alsoexpresses a Cinnamomum camphora C14-preferring thioesterase and asucrose invertase. In this case, the transgenic Prototheca cell producesa lipid profile that closely approximates the lipid profile found intallow. Tallow is typically derived from rendered beef or mutton fat, issolid at room temperature and is utilized in a variety of applicationsin the food, cosmetics, and chemicals industries. The fatty acid profileof tallow is: 4% C14:0; 26% C16:0; 3% C16:1; 14% C18:0; 41% C18:1; 3%C18:2; and 1% C18:3. As is shown in Example 6 below, clones oftransgenic Prototheca cells with a targeted ablation or knockout of anendogenous SAD and expressing a C. camphora C14-preferring thioesterasehave lipid profiles of: less than 1% C12 and shorter carbon chain lengthfatty acids; 2.74% to 6.13% C14:0; 23.07% to 25.69% C16:0; 7.02% to11.08% C18:0; 42.03% to 51.21% C18:1; and 9.37% to 13.45% C18:2(expressed in area percent). In some cases, the transgenic Protothecacells have lipid profiles of: 3-5% C14:0; 25-27% C16:0; 10-15% C18:0;and 40-45% C18:1.

In particular embodiments, microbes of the present invention aregenetically engineered to express one or more exogenous genes selectedfrom an acyl-ACP thioesterase, an acyl-CoA/aldehyde reductase, a fattyacyl-CoA reductase, a fatty aldehyde reductase, a fatty aldehydedecarbonylase, or a naturally co-expressed acyl carrier protein.Suitable expression methods are described above with respect to theexpression of a lipase gene, including, among other methods, inducibleexpression and compartmentalized expression. A fatty acyl-ACPthioesterase cleaves a fatty acid from an acyl carrier protein (ACP)during lipid synthesis. Through further enzymatic processing, thecleaved fatty acid is then combined with a coenzyme to yield an acyl-CoAmolecule. This acyl-CoA is the substrate for the enzymatic activity of afatty acyl-CoA reductase to yield an aldehyde, as well as for a fattyacyl-CoA/aldehyde reductase to yield an alcohol. The aldehyde producedby the action of the fatty acyl-CoA reductase identified above is thesubstrate for further enzymatic activity by either a fatty aldehydereductase to yield an alcohol, or a fatty aldehyde decarbonylase toyield an alkane or alkene.

In some embodiments, fatty acids, glycerolipids, or the correspondingprimary alcohols, aldehydes, alkanes or alkenes, generated by themethods described herein, contain 8, 10, 12, or 14 carbon atoms.Preferred fatty acids for the production of diesel, biodiesel, renewablediesel, or jet fuel, or the corresponding primary alcohols, aldehydes,alkanes and alkenes, for industrial applications contain 8 to 14 carbonatoms. In certain embodiments, the above fatty acids, as well as theother corresponding hydrocarbon molecules, are saturated (with nocarbon-carbon double or triple bonds); mono unsaturated (single doublebond); poly unsturated (two or more double bonds); are linear (notcyclic) or branched. For fuel production, greater saturation ispreferred.

The enzymes described directly above have a preferential specificity forhydrolysis of a substrate containing a specific number of carbon atoms.For example, a fatty acyl-ACP thioesterase may have a preference forcleaving a fatty acid having 12 carbon atoms from the ACP. In someembodiments, the ACP and the length-specific thioesterase may have anaffinity for one another that makes them particularly useful as acombination (e.g., the exogenous ACP and thioesterase genes may benaturally co-expressed in a particular tissue or organism from whichthey are derived). Therefore, in various embodiments, the recombinantPrototheca cell of the invention can contain an exogenous gene thatencodes a protein with specificity for catalyzing an enzymatic activity(e.g., cleavage of a fatty acid from an ACP, reduction of an acyl-CoA toan aldehyde or an alcohol, or conversion of an aldehyde to an alkane)with regard to the number of carbon atoms contained in the substrate.The enzymatic specificity can, in various embodiments, be for asubstrate having from 8 to 34 carbon atoms, preferably from 8 to 18carbon atoms, and more preferably from 8 to 14 carbon atoms. A preferredspecificity is for a substrate having fewer, i.e., 12, rather than more,i.e., 18, carbon atoms.

Other fatty acyl-ACP thioesterases suitable for use with the microbesand methods of the invention include, without limitation, those listedin Table 4.

TABLE 4 Fatty acyl-ACP thioesterases and GenBank accession numbers.Umbellularia californica fatty acyl-ACP thioesterase (GenBank #AAC49001)Cinnamomum camphora fatty acyl-ACP thioesterase (GenBank #Q39473)Umbellularia californica fatty acyl-ACP thioesterase (GenBank #Q41635)Myristica fragrans fatty acyl-ACP thioesterase (GenBank #AAB71729)Myristica fragrans fatty acyl-ACP thioesterase (GenBank #AAB71730)Elaeis guineensis fatty acyl-ACP thioesterase (GenBank #ABD83939) Elaeisguineensis fatty acyl-ACP thioesterase (GenBank #AAD42220) Elaeisguineensis fatty acyl-ACP thioesterase (GenBank#AAD42220.2) Populustomentosa fatty acyl-ACP thioesterase (GenBank #ABC47311) Arabidopsisthaliana fatty acyl-ACP thioesterase (GenBank #NP_172327) Arabidopsisthaliana fatty acyl-ACP thioesterase (GenBank #CAA85387) Arabidopsisthaliana fatty acyl-ACP thioesterase (GenBank #CAA85388) Gossypiumhirsutum fatty acyl-ACP thioesterase (GenBank #Q9SQI3) Cuphea lanceolatafatty acyl-ACP thioesterase (GenBank #CAA54060) Cuphea hookeriana fattyacyl-ACP thioesterase (GenBank #AAC72882) Cuphea calophylla subsp.mesostemon fatty acyl-ACP thioesterase (GenBank #ABB71581) Cuphealanceolata fatty acyl-ACP thioesterase (GenBank #CAC19933) Elaeisguineensis fatty acyl-ACP thioesterase (GenBank #AAL15645) Cupheahookeriana fatty acyl-ACP thioesterase (GenBank #Q39513) Cupheahookeriana fatty acyl-ACP thioesterase (GenBank#Q39513.1) Gossypiumhirsutum fatty acyl-ACP thioesterase (GenBank #AAD01982) Vitis viniferafatty acyl-ACP thioesterase (GenBank #CAN81819) Garcinia mangostanafatty acyl-ACP thioesterase (GenBank #AAB51525) Garcinia mangostanafatty acyl-ACP thioestease (GenBank#AAB51525.1) Brassica juncea fattyacyl-ACP thioesterase (GenBank #ABI18986) Madhuca longifolia fattyacyl-ACP thioesterase (GenBank #AAX51637) Brassica napus fatty acyl-ACPthioesterase (GenBank #ABH11710) Brassica napus fatty acyl-ACPthioesterase (GenBank#CAA52070.1) Oryza sativa (indica cultivar-group)fatty acyl-ACP thioesterase (GenBank #EAY86877) Oryza sativa (japonicacultivar-group) fatty acyl-ACP thioesterase (GenBank #NP_001068400)Oryza sativa (indica cultivar-group) fatty acyl-ACP thioesterase(GenBank #EAY99617) Cuphea hookeriana fatty acyl-ACP thioesterase(GenBank #AAC49269) Ulmus Americana fatty acyl-ACP thioesterase (GenBank#AAB71731) Cuphea lanceolata fatty acyl-ACP thioesterase (GenBank#CAB60830) Cuphea palustris fatty acyl-ACP thioesterase (GenBank#AAC49180) Iris germanica fatty acyl-ACP thioesterase (GenBank#AAG43858) Iris germanica fatty acyl-ACP thioesterase (GenBank#AAG43858.1) Cuphea palustris fatty acyl-ACP thioesterase (GenBank#AAC49179) Myristica fragrans fatty acyl-ACP thioesterase (GenBank#AAB71729) Myristica fragrans fatty acyl-ACP thioesterase (GenBank#AAB717291.1) Cuphea hookeriana fatty acyl-ACP thioesterase (GenBank#U39834) Umbelluaria californica fatty acyl-ACP thioesterase (GenBank #M94159) Cinnamomum camphora fatty acyl-ACP thioesterase (GenBank#U31813) Ricinus communis fatty acyl-ACP thioesterase(GenBank#ABS30422.1)

Examples below describe the successful targeting and expression ofheterologous fatty acyl-ACP thioesterases from Cuphea hookeriana,Umbellularia californica, Cinnamomun camphora, Cuphea palustris, Cuphealanceolata, Iris germanica, Myristica fragrans, Garcinia mangostana,Elaeis guiniensis, Brassica napus, Ricinus communis and Ulmus americanain Prototheca species. Additionally, alterations in fatty acid profileswere confirmed in the host cells expressing these heterologous fattyacyl-ACP thioesterases. As shown in the Examples, the expression ofthese heterologous thioesterases in Prototheca generates a transgenicmicroalgae that is able to produce oil/lipids with truly unique fattyacid profiles that are currently not available from commercial seedcrops, even through the blending of several seed crop oils. Table 5shows the fatty acid profiles of common commercial seed oils. Allcommercial seed oil data below were compiled from the US PharmacopeiasFood and Chemicals Codes, 7^(th) Ed. 2010-2011. Tallow data is from theNational Research Council: Fat Content and Composition of AnimalProducts (1976).

TABLE 5 Lipid profiles of commercial seed oils. C18:0- C18:1- C8:0 C10:0C12:0 C14:0 C16:0 C18:0 C18:1 diOH OH C18:2 C18:3 α R. communis 0 0 0 00.9-1.6  1.0-1.8 3.7-6.7 0.4-1.3 83.6-89.0 0 0.2-0.6 (Castor oil) C.nucifera 5.0-9.0 4.0-8.0 44-52 15-21 8.0-11.0 1.0-4.0 5.0-8.0 0 0  0-2.5 0 (Coconut oil) Z. mays 0 0 0 <1.0 8.0-19.0 0.5-4.0 19-50 0 038-65 <2.0 (Corn oil) G. barbadense 0 0 <0.1 0.5-2.0 17-29  1.0-4.013-44 0 0 40-63 0.1-2.1 (Cottonseed oil) B. rapa, B 0 0 <0.1 <0.2 <6.0<2.5 >50 0 0 <40 <14 napus, B. juncea (Canola) O. europea 0 0 0 <0.16.5-20.0 0.5-5.0 56-85 0 0  3.5-20.0 <1.2 (Olive) A. hypogaea 0 0 <0.1<0.2 7.0-16.0 1.3-6.5 35-72 0 0 13.0-43   <0.6 (Peanut) E. guineensis3.0-5.0 2.5-6.0 40-52 14.0-18.0 7.0-10.0 1.0-3.0 11.0-19.0 0 0 0.5-4.0 0(Palm kernel) E. guineensis 0 0 0 0.5-5.9 32.0-47.0  2.0-8.0 34-44 0 0 7.2-12.0 0 (Palm) C. tinctorus 0 0 <0.1 <0.1 2.0-10.0  1.0-10.0 7.0-16.0 0 0 72-81 <1.5 (Safflower) H. annus 0 0 <0.1 <0.5 3.0-10.0 1.0-10.0 14-65 0 0 20-75 <0.5 (Sunflower) G. max 0 0 <0.1 <0.5 7.0-12.02.0-5.5 19-30 0 0 48-65  5.0-10.0 (Soybean) L. 0 0 <0.1 <0.5 2.0-9.0 2.0-5.0 8.0-60  0 0 40-80 <5.0 usitatissimum (Solin-Flax) B. parkii 0 00 0 3.8-4.1  41.2-56.8 34.0-46.9 0 0 3.7-6.5 0 (Sheanut) Tallow 4 26 1441 3 1

As an example, none of these common seed oils contain high amounts of C8or C10 fatty acids, with coconut oil and palm kernel oil being thelargest sources, but both having a ratio of about 1:1 (C8:C10 fattyacids). As shown in the Examples, Prototheca transformed with Cupheapalustris C:8 preferring thioesterase was able to achieve not only a C8fatty acid levels of over 12%, but also, the ratio of C8:C10 fatty acidswas about 5:1. Changes in fatty acid levels are useful for producingoils containing a tailored fatty acid profile for a variety ofcommercial applications. Additionally, changes of ratios betweendifferent fatty acid chain lengths is something has not been availablecommercially in oils that have not undergone further costly chemicalprocesses (such as esterification, distillation, fractionation, andre-esterification). As another example, palm oil is the highest C16:0fatty acid (32-47%) containing oil, but palm oil has very little C14:0fatty acids. Prototheca containing the U. americana thioesteraseachieved about 33-38% C16:0 fatty acids and about a 10-16% C14:0 fattyacids (about a 2:1 C16:0 to C14:0 ratio). This fatty acid profile hasbeen commercially impractical through blending of existing oils at acommercial level because the seed oils that are high in 16:0 fatty acidsusually do not contain much 14:0 fatty acids.

The Examples below also describe, the successful targeting andexpression of at least two fatty acyl-ACP thioesterases in one clone.The alterations in the fatty acid profiles were confirmed in theseclones and depending on which two thioesterases were co-expressed in oneclone, the fatty acid profiles were impacted in different ways. As anexample, from Table 5 above, both coconut oil and palm kernel oil haveC12:C14 ratios of roughly 3:1. As described in the Examples below, aPrototheca transformant containing two heterologous thioesterase geneswas able to produce C12:C14 fatty acid levels at a ratio of roughly 5:1.This kind of ratio of C12:C14 fatty acids has been commerciallyimpractical (i.e., through blending of seed oils).

Another novel aspect of the oils produced by transgenic microalgae isthe degree of saturation of the fatty acids. Palm oil is currently thelargest source of saturated oil, with a total saturates to unsaturatesof 52% to 48%. As shown in the Examples below, Prototheca withheterologous thioesterases from U. americana and C. camphora achievedtotal saturates levels of over 60% in the oil that it produced. Alsoshown in the Examples below, Prototheca with heterologous thioesterasefrom U. americana achieved total saturates level of over 86% in the oilthat it produced.

Fatty acyl-CoA/aldehyde reductases suitable for use with the microbesand methods of the invention include, without limitation, those listedin Table 6.

TABLE 6 Fatty acyl-CoA/aldehyde reductases listed by GenBank accessionnumbers. AAC45217, YP_047869, BAB85476, YP_001086217, YP_580344,YP_001280274, YP_264583, YP_436109, YP_959769, ZP_01736962, ZP_01900335,ZP_01892096, ZP_01103974, ZP_01915077, YP_924106, YP_130411,ZP_01222731, YP_550815, YP_983712, YP_001019688, YP_524762, YP_856798,ZP_01115500, YP_001141848, NP_336047, NP_216059, YP_882409, YP_706156,YP_001136150, YP_952365, ZP_01221833, YP_130076, NP_567936, AAR88762,ABK28586, NP_197634, CAD30694, NP_001063962, BAD46254, NP_001030809,EAZ10132, EAZ43639, EAZ07989, NP_001062488, CAB88537, NP_001052541,CAH66597, CAE02214, CAH66590, CAB88538, EAZ39844, AAZ06658, CAA68190,CAA52019, and BAC84377

Fatty acyl-CoA reductases suitable for use with the microbes and methodsof the invention include, without limitation, those listed in Table 7.

TABLE 7 Fatty acyl-CoA reductases listed by GenBank accession numbers.NP_187805, ABO14927, NP_001049083, CAN83375, NP_191229, EAZ42242,EAZ06453, CAD30696, BAD31814, NP_190040, AAD38039, CAD30692, CAN81280,NP_197642, NP_190041, AAL15288, and NP_190042

Fatty aldehyde decarbonylases suitable for use with the microbes andmethods of the invention include, without limitation, those listed inTable 8.

TABLE 8 Fatty aldehyde decarbonylases listed by GenBank accessionnumbers. NP_850932, ABN07985, CAN60676, AAC23640, CAA65199, AAC24373,CAE03390, ABD28319, NP_181306, EAZ31322, CAN63491, EAY94825, EAY86731,CAL55686, XP_001420263, EAZ23849, NP_200588, NP_001063227, CAN83072,AAR90847, and AAR97643

Combinations of naturally co-expressed fatty acyl-ACP thioesterases andacyl carrier proteins are suitable for use with the microbes and methodsof the invention.

Additional examples of hydrocarbon or lipid modification enzymes includeamino acid sequences contained in, referenced in, or encoded by nucleicacid sequences contained or referenced in, any of the following U.S.Pat. Nos. 6,610,527; 6,451,576; 6,429,014; 6,342,380; 6,265,639;6,194,185; 6,114,160; 6,083,731; 6,043,072; 5,994,114; 5,891,697;5,871,988; 6,265,639, and further described in GenBank Accessionnumbers: AAO18435; ZP_00513891; Q38710; AAK60613; AAK60610; AAK60611;NP_113747; CAB75874; AAK60612; AAF20201; BAA11024; AF205791; andCAA03710.

Other enzymes in the lipid biosynthetic pathways are also suitable foruse with microbes and methods of the invention. For example, ketoacyl-ACP synthase (Kas) enzymes work in conjunction with some of theabove listed enzymes in the lipid biosynthetic pathway. There differentclasses of Kas enzymes: Kas I participates in successive condensationsteps between the ever-growing acyl ACP chains and malonyl-ACP. Kas IItypically participates in the final condensation step leading fromC16:0-ACP to C18:0-ACP incorporating malonyl-ACP. As such, in higherplants and some microalgae species/strains that synthesize predominantlyC16-C18:0 fatty acids (and their unsaturated derivatives), Kas IIenzymes interact with products of FatA genes (acyl-ACP thioesterases).

Acyl-ACP liberate growing fatty acid chains from ACP during fatty acidbiosynthesis, and in most plant species, this is carried out by membersof the FatA gene family, whose role is to terminate elongation at theC16:0 to C18:0 stage. In species that synthesize shorter chain fattyacids (such as Cuphea, Elaeis, Myristica, or Umbellularia), a differentgroup of acyl-ACP thioesterases encoded by FatB genes carry out thistermination step. The interaction between Kas II enzymes and acyl-Acpthioesterases is important for the correct termination of fatty acidchain elongation. As a consequence, in higher plant species (andmicroalgal species) that have evolved FatB genes capable of shorterchain lipid biosynthesis, there has been a corresponding co-evolution ofan additional class of Kas genes, termed Kas IV genes. Kas IV genes areresponsible for chain length elongation of a specific size range offatty acids, 4-14 carbons in length.

Other suitable enzymes for use with the microbes and the methods of theinvention include those that have at least 70% amino acid identity withone of the proteins listed in Tables 4, 6-8, and that exhibit thecorresponding desired enzymatic activity (e.g., cleavage of a fatty acidfrom an acyl carrier protein, reduction of an acyl-CoA to an aldehyde oran alcohol, or conversion of an aldehyde to an alkane). In additionalembodiments, the enzymatic activity is present in a sequence that has atleast about 75%, at least about 80%, at least about 85%, at least about90%, at least about 95%, or at least about 99% identity with one of theabove described sequences, all of which are hereby incorporated byreference as if fully set forth.

By selecting the desired combination of exogenous genes to be expressed,one can tailor the product generated by the microbe, which may then beextracted from the aqueous biomass. For example, the microbe can containone or more of (i) an exogenous gene encoding a fatty acyl-ACPthioesterase; and, optionally, (ii) a naturally co-expressed acylcarrier protein or an acyl carrier protein otherwise having affinity forthe fatty acyl-ACP thioesterase (or conversely); and, optionally, (iii)an exogenous gene encoding a fatty acyl-CoA/aldehyde reductase or afatty acyl-CoA reductase; and, optionally, (iv) an exogenous geneencoding a fatty aldehyde reductase or a fatty aldehyde decarbonylase.The microbe can also contain one or more of an exogenous stearoil ACPdesturase, fatty acid destaurase, β-ketoacyl-ACP synthase I (e.g. asencoded by a KASI gene), a β-ketoacyl-ACP synthase II (e.g. as encodedby a KASII gene), or oleate-12 hydroxylase. The microbe, under cultureconditions described herein, synthesizes a fatty acid linked to an ACPand the fatty acyl-ACP thioesterase catalyzes the cleavage of the fattyacid from the ACP to yield, through further enzymatic processing, afatty acyl-CoA molecule. When present, the fatty acyl-CoA/aldehydereducatase catalyzes the reduction of the acyl-CoA to an alcohol.Similarly, the fatty acyl-CoA reductase, when present, catalyzes thereduction of the acyl-CoA to an aldehyde. In those embodiments in whichan exogenous gene encoding a fatty acyl-CoA reductase is present andexpressed to yield an aldehyde product, a fatty aldehyde reductase,encoded by the third exogenous gene, catalyzes the reduction of thealdehyde to an alcohol. Similarly, a fatty aldehyde decarbonylasecatalyzes the conversion of the aldehyde to an alkane or an alkene, whenpresent.

In another embodiment, the microbe can contain: (i) an exogenous geneencoding a fatty acyl-ACP thioesterase; (ii) optionally, a naturallyco-expressed acyl carrier protein or an acyl carrier protein havingaffinity for the fatty acid acyl-ACP thioesterase; (iii) a mutatedendogenous desaturase gene, wherein the mutation renders the desaturasegene or desaturase protein inactive, such as a desaturase knockout or adesturase suppression element such as a targeted RNAi, antisense ordsRNA construct; (iv) overexpression of an endogenous stearoyl acylcarrier protein desaturase or the expression of a heterologous SAD; and(v) any combination of the foregoing.

Genes encoding such enzymes, such as fatty acyl ACP thioesterases, canbe obtained from cells already known to exhibit significant lipidproduction such as Chlorella protothecoides. Genes already known to havea role in lipid production, e.g., a gene encoding an enzyme thatsaturates double bonds, can be transformed individually into recipientcells. However, to practice the invention it is not necessary to make apriori assumptions as to which genes are required. Methods foridentifying genes that can alter (improve) lipid production inmicroalgae are described in PCT Pub. No. 2008/151149.

Thus, the present invention provides a Prototheca cell that has beengenetically engineered to express a lipid pathway enzyme at an alteredlevel compared to a wild-type cell of the same species. In some cases,the cell produces more lipid compared to the wild-type cell when bothcells are grown under the same conditions. In some cases, the cell hasbeen genetically engineered and/or selected to express a lipid pathwayenzyme at a higher level or a lower level than the wild-type cell. Insome cases, the lipid pathway enzyme is selected from the groupconsisting of pyruvate dehydrogenase, acetyl-CoA carboxylase, acylcarrier protein, and glycerol-3 phosphate acyltransferase. In somecases, the cell has been genetically engineered and/or selected toexpress a lipid pathway enzyme at a lower level than the wild-type cell.In at least one embodiment in which the cell expresses the lipid pathwayenzyme at a lower level, the lipid pathway enzyme comprises citratesynthase.

In some embodiments, the cell has been genetically engineered and/orselected to express a global regulator of fatty acid synthesis at analtered level compared to the wild-type cell, whereby the expressionlevels of a plurality of fatty acid synthetic genes are altered comparedto the wild-type cell. In some cases, the lipid pathway enzyme comprisesan enzyme that modifies a fatty acid. In some cases, the lipid pathwayenzyme is selected from a stearoyl-ACP desaturase and a glycerolipiddesaturase. In some cases, the cell has been genetically engineeredand/or selected to express a lower level of a lipid pathway enzyme, ornot to express a specific lipid pathway enzyme at all (i.e., wherein alipid pathway enzyme has been knockout, replaced with an exogenous gene,or expression has been reduced using RNAi or antisense methods). Inanother embodiment, the lipid pathway enzyme is the heterologousexpression of a desaturase gene, including but not limited to astearoyl-ACP desaturase or a fatty acid desaturase (FAD). Example 6describes the expression of a heterologous stearoyl-ACP from Oleaeuropaea in a Prototheca moriformis genetic background.

In other embodiments, the present invention is directed to anoil-producing microbe containing one or more exogenous genes, whereinthe exogenous genes encode protein(s) selected from the group consistingof a fatty acyl-ACP thioesterase, a fatty acyl-CoA reductase, a fattyaldehyde reductase, a fatty acyl-CoA/aldehyde reductase, a fattyaldehyde decarbonylase, a desaturase, and an acyl carrier protein. Inanother embodiment, an endogenous desaturase gene is overexpressed in amicrobe containing one or more of the above exogenous genes. In oneembodiment, the exogenous gene is in operable linkage with a promoter,which is inducible or repressible in response to a stimulus. In somecases, the stimulus is selected from the group consisting of anexogenously provided small molecule, heat, cold, and limited or nonitrogen in the culture media. In some cases, the exogenous gene isexpressed in a cellular compartment. In some embodiments, the cellularcompartment is selected from the group consisting of a chloroplast, aplastid and a mitochondrion. In some embodiments the microbe isPrototheca moriformis, Prototheca krugani, Prototheca stagnora orPrototheca zopfii.

In one embodiment, the exogenous gene encodes a fatty acid acyl-ACPthioesterase. In some cases, the thioesterase encoded by the exogenousgene catalyzes the cleavage of an 8 to 18-carbon fatty acid from an acylcarrier protein (ACP). In some cases, the thioesterase encoded by theexogenous gene catalyzes the cleavage of a 10 to 14-carbon fatty acidfrom an ACP. In one embodiment, the thioesterase encoded by theexogenous gene catalyzes the cleavage of a 12-carbon fatty acid from anACP.

In one embodiment, the exogenous gene encodes a fatty acyl-CoA/aldehydereductase. In some cases, the reductase encoded by the exogenous genecatalyzes the reduction of an 8 to 18-carbon fatty acyl-CoA to acorresponding primary alcohol. In some cases, the reductase encoded bythe exogenous gene catalyzes the reduction of a 10 to 14-carbon fattyacyl-CoA to a corresponding primary alcohol. In one embodiment, thereductase encoded by the exogenous gene catalyzes the reduction of a12-carbon fatty acyl-CoA to dodecanol.

The present invention also provides a recombinant Prototheca or othercell containing two exogenous genes, wherein a first exogenous geneencodes a fatty acyl-ACP thioesterase and a second exogenous geneencodes a protein selected from the group consisting of a fatty acyl-CoAreductase, a fatty acyl-CoA/aldehyde reductase, and an acyl carrierprotein. In some cases, the two exogenous genes are each in operablelinkage with a promoter, which is inducible in response to a stimulus.In some cases, each promoter is inducible in response to an identicalstimulus, such as limited or no nitrogen in the culture media.Limitation or complete lack of nitrogen in the culture media stimulatesoil production in some microorganisms such as Prototheca species, andcan be used as a trigger to induce oil production to high levels. Whenused in combination with the genetic engineering methods disclosedherein, the lipid as a percentage of dry cell weight can be pushed tohigh levels such as at least 30%, at least 40%, at least 50%, at least60%, at least 70% at least 75%, at least 80%, at least 85% or between 75to 90%; methods disclosed herein provide for cells with these levels oflipid, wherein the lipid is at least 4% C8-C14, at least 0.3% C8, atleast 2% C10, at least 2% C12, and at least 2% C14. In some embodimentsthe cells are over 25% lipid by dry cell weight and contain lipid thatis at least 10% C8-C14, at least 20% C8-C14, at least 30% C8-C14, 10-30%C8-C14 and 20-30% C8-C14.

The novel oils disclosed herein are distinct from other naturallyoccurring oils that are high in mid-chain fatty acids, such as palm oil,palm kernel oil, and coconut oil. For example, levels of contaminantssuch as carotenoids are far higher in palm oil and palm kernel oil thanin the oils of the invention. Palm and palm kernel oils in particularcontain alpha and beta carotenes and lycopene in much higher amountsthan is in the oils of the invention. In addition, over 20 differentcarotenoids are found in palm and palm kernel oil, whereas the Examplesdemonstrate that the oils of the invention contain very few carotenoidsspecies and very low levels. In addition, the levels of vitamin Ecompounds such as tocotrienols are far higher in palm, palm kernel, andcoconut oil than in the oils of the invention.

In one embodiment, the thioesterase encoded by the first exogenous genecatalyzes the cleavage of an 8 to 18-carbon fatty acid from an ACP. Insome embodiments, the second exogenous gene encodes a fattyacyl-CoA/aldehyde reductase which catalyzes the reduction of an 8 to18-carbon fatty acyl-CoA to a corresponding primary alcohol. In somecases, the thioesterase encoded by the first exogenous gene catalyzesthe cleavage of a 10 to 14-carbon fatty acid from an ACP, and thereductase encoded by the second exogenous gene catalyzes the reductionof a 10 to 14-carbon fatty acyl-CoA to the corresponding primaryalcohol, wherein the thioesterase and the reductase act on the samecarbon chain length. In one embodiment, the thioesterase encoded by thefirst exogenous gene catalyzes the cleavage of a 12-carbon fatty acidfrom an ACP, and the reductase encoded by the second exogenous genecatalyzes the reduction of a 12-carbon fatty acyl-CoA to dodecanol. Insome embodiments, the second exogenous gene encodes a fatty acyl-CoAreductase which catalyzes the reduction of an 8 to 18-carbon fattyacyl-CoA to a corresponding aldehyde. In some embodiments, the secondexogenous gene encodes an acyl carrier protein that is naturallyco-expressed with the fatty acyl-ACP thioesterase.

In some embodiments, the second exogenous gene encodes a fatty acyl-CoAreductase, and the microbe further contains a third exogenous geneencoding a fatty aldehyde decarbonylase. In some cases, the thioesteraseencoded by the first exogenous gene catalyzes the cleavage of an 8 to18-carbon fatty acid from an ACP, the reductase encoded by the secondexogenous gene catalyzes the reduction of an 8 to 18-carbon fattyacyl-CoA to a corresponding fatty aldehyde, and the decarbonylaseencoded by the third exogenous gene catalyzes the conversion of an 8 to18-carbon fatty aldehyde to a corresponding alkane, wherein thethioesterase, the reductase, and the decarbonylase act on the samecarbon chain length.

In some embodiments, the second exogenous gene encodes an acyl carrierprotein, and the microbe further contains a third exogenous geneencoding a protein selected from the group consisting of a fattyacyl-CoA reductase and a fatty acyl-CoA/aldehyde reductase. In somecases, the third exogenous gene encodes a fatty acyl-CoA reductase, andthe microbe further contains a fourth exogenous gene encoding a fattyaldehyde decarbonylase.

The present invention also provides methods for producing an alcoholcomprising culturing a population of recombinant Prototheca cells in aculture medium, wherein the cells contain (i) a first exogenous geneencoding a fatty acyl-ACP thioesterase, and (ii) a second exogenous geneencoding a fatty acyl-CoA/aldehyde reductase, and the cells synthesize afatty acid linked to an acyl carrier protein (ACP), the fatty acyl-ACPthioesterase catalyzes the cleavage of the fatty acid from the ACP toyield, through further processing, a fatty acyl-CoA, and the fattyacyl-CoA/aldehyde reductase catalyzes the reduction of the acyl-CoA toan alcohol.

The present invention also provides methods of producing a lipidmolecule in a Prototheca cell. In one embodiment, the method comprisesculturing a population of Prototheca cells in a culture medium, whereinthe cells contain (i) a first exogenous gene encoding a fatty acyl-ACPthioesterase, and (ii) a second exogenous gene encoding a fatty acyl-CoAreductase, and wherein the microbes synthesize a fatty acid linked to anacyl carrier protein (ACP), the fatty acyl-ACP thioesterase catalyzesthe cleavage of the fatty acid from the ACP to yield, through furtherprocessing, a fatty acyl-CoA, and the fatty acyl-CoA reductase catalyzesthe reduction of the acyl-CoA to an aldehyde.

The present invention also provides methods of producing a fatty acidmolecule having a specified carbon chain length in a Prototheca cell. Inone embodiment, the method comprises culturing a population oflipid-producing Prototheca cells in a culture medium, wherein themicrobes contain an exogenous gene encoding a fatty acyl-ACPthioesterase having an activity specific or preferential to a certaincarbon chain length, such as 8, 10, 12 or 14 carbon atoms, and whereinthe microbes synthesize a fatty acid linked to an acyl carrier protein(ACP) and the thioesterase catalyzes the cleavage of the fatty acid fromthe ACP when the fatty acid has been synthesized to the specific carbonchain length.

In the various embodiments described above, the Prototheca cell cancontain at least one exogenous gene encoding a lipid pathway enzyme or asuppression element such as an RNA interference element that suppressesexpression of the gene product. In some cases, the lipid pathway enzymeis selected from the group consisting of a stearoyl-ACP desaturase, aglycerolipid desaturase, a pyruvate dehydrogenase, an acetyl-CoAcarboxylase, an acyl carrier protein, and a glycerol-3 phosphateacyltransferase. In other cases, the Prototheca cell contains a lipidmodification enzyme selected from the group consisting of a fattyacyl-ACP thioesterase, a fatty acyl-CoA/aldehyde reductase, a fattyacyl-CoA reductase, a fatty aldehyde reductase, a fatty aldehydedecarbonylase, and/or an acyl carrier protein.

The present invention also provides for a microbial cell that contains aheterologous gene that encodes a hydroxylase that generates ahydroxylated fatty acid. The microbial cell may comprise a type II fattyacid synthesis pathway. For example, the microbial cell may be amicroalgal cell. In some embodiments, the microalgal cell is selectedfrom the microalgal cells listed in Table 1 above. In other embodimentsthe microalgal cell is of the genus Prototheca. In still otherembodiments, the microalgal cell is Prototheca moriformis. Hydroxylasesare enzymes that adds a hydroxyl group (—OH) onto a substrate. Fattyacid hydroxylases are naturally occurring enzymes found in some higherplants. A non-limiting example of a naturally occurring hydroxylasefound in a higher plant is the oleate 12-hydroxylase from Ricinuscommunis which is responsible for the production of ricinoleic acid.Example 7 describes an example of the heterologous expression of ahydroxylase in Prototheca cells, specifically, the expression of Ricinuscommunis oleate 12-hydroxlase in Prototheca moriformis cells.

VI. FUELS AND CHEMICALS PRODUCTION

For the production of fuel in accordance with the methods of theinvention lipids produced by cells of the invention are harvested, orotherwise collected, by any convenient means. Lipids can be isolated bywhole cell extraction. The cells are first disrupted, and thenintracellular and cell membrane/cell wall-associated lipids as well asextracellular hydrocarbons can be separated from the cell mass, such asby use of centrifugation as described above. Intracellular lipidsproduced in microorganisms are, in some embodiments, extracted afterlysing the cells of the microorganism. Once extracted, the lipids arefurther refined to produce oils, fuels, or oleochemicals.

After completion of culturing, the microorganisms can be separated fromthe fermentation broth. Optionally, the separation is effected bycentrifugation to generate a concentrated paste. Centrifugation does notremove significant amounts of intracellular water from themicroorganisms and is not a drying step. The biomass can then optionallybe washed with a washing solution (e.g., DI water) to get rid of thefermentation broth and debris. Optionally, the washed microbial biomassmay also be dried (oven dried, lyophilized, etc.) prior to celldisruption. Alternatively, cells can be lysed without separation fromsome or all of the fermentation broth when the fermentation is complete.For example, the cells can be at a ratio of less than 1:1 v:v cells toextracellular liquid when the cells are lysed.

Microorganisms containing a lipid can be lysed to produce a lysate. Asdetailed herein, the step of lysing a microorganism (also referred to ascell lysis) can be achieved by any convenient means, includingheat-induced lysis, adding a base, adding an acid, using enzymes such asproteases and polysaccharide degradation enzymes such as amylases, usingultrasound, mechanical lysis, using osmotic shock, infection with alytic virus, and/or expression of one or more lytic genes. Lysis isperformed to release intracellular molecules which have been produced bythe microorganism. Each of these methods for lysing a microorganism canbe used as a single method or in combination simultaneously orsequentially. The extent of cell disruption can be observed bymicroscopic analysis. Using one or more of the methods described herein,typically more than 70% cell breakage is observed. Preferably, cellbreakage is more than 80%, more preferably more than 90% and mostpreferred about 100%.

In particular embodiments, the microorganism is lysed after growth, forexample to increase the exposure of cellular lipid and/or hydrocarbonfor extraction or further processing. The timing of lipase expression(e.g., via an inducible promoter) or cell lysis can be adjusted tooptimize the yield of lipids and/or hydrocarbons. Below are described anumber of lysis techniques. These techniques can be used individually orin combination.

In one embodiment of the present invention, the step of lysing amicroorganism comprises heating of a cellular suspension containing themicroorganism. In this embodiment, the fermentation broth containing themicroorganisms (or a suspension of microorganisms isolated from thefermentation broth) is heated until the microorganisms, i.e., the cellwalls and membranes of microorganisms degrade or breakdown. Typically,temperatures applied are at least 50° C. Higher temperatures, such as,at least 30° C. at least 60° C., at least 70° C., at least 80° C., atleast 90° C., at least 100° C., at least 110° C., at least 120° C., atleast 130° C. or higher are used for more efficient cell lysis. Lysingcells by heat treatment can be performed by boiling the microorganism.Alternatively, heat treatment (without boiling) can be performed in anautoclave. The heat treated lysate may be cooled for further treatment.Cell disruption can also be performed by steam treatment, i.e., throughaddition of pressurized steam. Steam treatment of microalgae for celldisruption is described, for example, in U.S. Pat. No. 6,750,048. Insome embodiments, steam treatment may be achieved by sparging steam intothe fermentor and maintaining the broth at a desired temperature forless than about 90 minutes, preferably less than about 60 minutes, andmore preferably less than about 30 minutes.

In another embodiment of the present invention, the step of lysing amicroorganism comprises adding a base to a cellular suspensioncontaining the microorganism. The base should be strong enough tohydrolyze at least a portion of the proteinaceous compounds of themicroorganisms used. Bases which are useful for solubilizing proteinsare known in the art of chemistry. Exemplary bases which are useful inthe methods of the present invention include, but are not limited to,hydroxides, carbonates and bicarbonates of lithium, sodium, potassium,calcium, and mixtures thereof. A preferred base is KOH. Base treatmentof microalgae for cell disruption is described, for example, in U.S.Pat. No. 6,750,048.

In another embodiment of the present invention, the step of lysing amicroorganism comprises adding an acid to a cellular suspensioncontaining the microorganism. Acid lysis can be effected using an acidat a concentration of 10-500 mN or preferably 40-160 nM. Acid lysis ispreferably performed at above room temperature (e.g., at 40-160°, andpreferably a temperature of 50-1300. For moderate temperatures (e.g.,room temperature to 100° C. and particularly room temperature to 650,acid treatment can usefully be combined with sonication or other celldisruption methods.

In another embodiment of the present invention, the step of lysing amicroorganism comprises lysing the microorganism by using an enzyme.Preferred enzymes for lysing a microorganism are proteases andpolysaccharide-degrading enzymes such as hemicellulase (e.g.,hemicellulase from Aspergillus niger; Sigma Aldrich, St. Louis, Mo.;#H2125), pectinase (e.g., pectinase from Rhizopus sp.; Sigma Aldrich,St. Louis, Mo.; #P2401), Mannaway 4.0 L (Novozymes), cellulase (e.g.,cellulose from Trichoderma viride; Sigma Aldrich, St. Louis, Mo.;#C9422), and driselase (e.g., driselase from Basidiomycetes sp.; SigmaAldrich, St. Louis, Mo.; #D9515.

In other embodiments of the present invention, lysis is accomplishedusing an enzyme such as, for example, a cellulase such as apolysaccharide-degrading enzyme, optionally from Chlorella or aChlorella virus, or a proteases, such as Streptomyces griseus protease,chymotrypsin, proteinase K, proteases listed in Degradation ofPolylactide by Commercial Proteases, Oda Y et al., Journal of Polymersand the Environment, Volume 8, Number 1, January 2000, pp. 29-32(4),Alcalase 2.4 FG (Novozymes), and Flavourzyme 100 L (Novozymes). Anycombination of a protease and a polysaccharide-degrading enzyme can alsobe used, including any combination of the preceding proteases andpolysaccharide-degrading enzymes.

In another embodiment, lysis can be performed using an expeller press.In this process, biomass is forced through a screw-type device at highpressure, lysing the cells and causing the intracellular lipid to bereleased and separated from the protein and fiber (and other components)in the cell.

In another embodiment of the present invention, the step of lysing amicroorganism is performed by using ultrasound, i.e., sonication. Thus,cells can also by lysed with high frequency sound. The sound can beproduced electronically and transported through a metallic tip to anappropriately concentrated cellular suspension. This sonication (orultrasonication) disrupts cellular integrity based on the creation ofcavities in cell suspension.

In another embodiment of the present invention, the step of lysing amicroorganism is performed by mechanical lysis. Cells can be lysedmechanically and optionally homogenized to facilitate hydrocarbon (e.g.,lipid) collection. For example, a pressure disrupter can be used to pumpa cell containing slurry through a restricted orifice valve. Highpressure (up to 1500 bar) is applied, followed by an instant expansionthrough an exiting nozzle. Cell disruption is accomplished by threedifferent mechanisms: impingement on the valve, high liquid shear in theorifice, and sudden pressure drop upon discharge, causing an explosionof the cell. The method releases intracellular molecules. Alternatively,a ball mill can be used. In a ball mill, cells are agitated insuspension with small abrasive particles, such as beads. Cells breakbecause of shear forces, grinding between beads, and collisions withbeads. The beads disrupt the cells to release cellular contents. Cellscan also be disrupted by shear forces, such as with the use of blending(such as with a high speed or Waring blender as examples), the frenchpress, or even centrifugation in case of weak cell walls, to disruptcells.

In another embodiment of the present invention, the step of lysing amicroorganism is performed by applying an osmotic shock.

In another embodiment of the present invention, the step of lysing amicroorganism comprises infection of the microorganism with a lyticvirus. A wide variety of viruses are known to lyse microorganismssuitable for use in the present invention, and the selection and use ofa particular lytic virus for a particular microorganism is within thelevel of skill in the art. For example, paramecium bursaria chlorellavirus (PBCV-1) is the prototype of a group (family Phycodnaviridae,genus Chlorovirus) of large, icosahedral, plaque-forming,double-stranded DNA viruses that replicate in, and lyse, certainunicellular, eukaryotic chlorella-like green algae. Accordingly, anysusceptible microalgae can be lysed by infecting the culture with asuitable chlorella virus. Methods of infecting species of Chlorella witha chlorella virus are known. See for example Adv. Virus Res. 2006;66:293-336; Virology, 1999 Apr. 25; 257(1):15-23; Virology, 2004 Jan. 5;318(1):214-23; Nucleic Acids Symp. Ser. 2000; (44):161-2; J. Virol. 2006March; 80(5):2437-44; and Annu. Rev. Microbiol. 1999; 53:447-94.

In another embodiment of the present invention, the step of lysing amicroorganism comprises autolysis. In this embodiment, a microorganismaccording to the invention is genetically engineered to produce a lyticprotein that will lyse the microorganism. This lytic gene can beexpressed using an inducible promoter so that the cells can first begrown to a desirable density in a fermentor, followed by induction ofthe promoter to express the lytic gene to lyse the cells. In oneembodiment, the lytic gene encodes a polysaccharide-degrading enzyme. Incertain other embodiments, the lytic gene is a gene from a lytic virus.Thus, for example, a lytic gene from a Chlorella virus can be expressedin an algal cell; see Virology 260, 308-315 (1999); FEMS MicrobiologyLetters 180 (1999) 45-53; Virology 263, 376-387 (1999); and Virology230, 361-368 (1997). Expression of lytic genes is preferably done usingan inducible promoter, such as a promoter active in microalgae that isinduced by a stimulus such as the presence of a small molecule, light,heat, and other stimuli.

Various methods are available for separating lipids from cellularlysates produced by the above methods. For example, lipids and lipidderivatives such as fatty aldehydes, fatty alcohols, and hydrocarbonssuch as alkanes can be extracted with a hydrophobic solvent such ashexane (see Frenz et al. 1989, Enzyme Microb. Technol., 11:717). Lipidsand lipid derivatives can also be extracted using liquefaction (see forexample Sawayama et al. 1999, Biomass and Bioenergy 17:33-39 and Inoueet al. 1993, Biomass Bioenergy 6(4):269-274); oil liquefaction (see forexample Minowa et al. 1995, Fuel 74(12):1735-1738); and supercriticalCO₂ extraction (see for example Mendes et al. 2003, Inorganica ChimicaActa 356:328-334). Miao and Wu describe a protocol of the recovery ofmicroalgal lipid from a culture of Chlorella prototheocoides in whichthe cells were harvested by centrifugation, washed with distilled waterand dried by freeze drying. The resulting cell powder was pulverized ina mortar and then extracted with n-hexane. Miao and Wu, BiosourceTechnology (2006) 97:841-846.

Thus, lipids, lipid derivatives and hydrocarbons generated by themicroorganisms of the present invention can be recovered by extractionwith an organic solvent. In some cases, the preferred organic solvent ishexane. Typically, the organic solvent is added directly to the lysatewithout prior separation of the lysate components. In one embodiment,the lysate generated by one or more of the methods described above iscontacted with an organic solvent for a period of time sufficient toallow the lipid and/or hydrocarbon components to form a solution withthe organic solvent. In some cases, the solution can then be furtherrefined to recover specific desired lipid or hydrocarbon components.Hexane extraction methods are well known in the art.

Lipids and lipid derivatives such as fatty aldehydes, fatty alcohols,and hydrocarbons such as alkanes produced by cells as described hereincan be modified by the use of one or more enzymes, including a lipase,as described above. When the hydrocarbons are in the extracellularenvironment of the cells, the one or more enzymes can be added to thatenvironment under conditions in which the enzyme modifies thehydrocarbon or completes its synthesis from a hydrocarbon precursor.Alternatively, the hydrocarbons can be partially, or completely,isolated from the cellular material before addition of one or morecatalysts such as enzymes. Such catalysts are exogenously added, andtheir activity occurs outside the cell or in vitro.

Thus, lipids and hydrocarbons produced by cells in vivo, orenzymatically modified in vitro, as described herein can be optionallyfurther processed by conventional means. The processing can include“cracking” to reduce the size, and thus increase the hydrogen:carbonratio, of hydrocarbon molecules. Catalytic and thermal cracking methodsare routinely used in hydrocarbon and triglyceride oil processing.Catalytic methods involve the use of a catalyst, such as a solid acidcatalyst. The catalyst can be silica-alumina or a zeolite, which resultin the heterolytic, or asymmetric, breakage of a carbon-carbon bond toresult in a carbocation and a hydride anion. These reactiveintermediates then undergo either rearrangement or hydride transfer withanother hydrocarbon. The reactions can thus regenerate the intermediatesto result in a self-propagating chain mechanism. Hydrocarbons can alsobe processed to reduce, optionally to zero, the number of carbon-carbondouble, or triple, bonds therein. Hydrocarbons can also be processed toremove or eliminate a ring or cyclic structure therein. Hydrocarbons canalso be processed to increase the hydrogen:carbon ratio. This caninclude the addition of hydrogen (“hydrogenation”) and/or the “cracking”of hydrocarbons into smaller hydrocarbons.

Thermal methods involve the use of elevated temperature and pressure toreduce hydrocarbon size. An elevated temperature of about 800° C. andpressure of about 700 kPa can be used. These conditions generate“light,” a term that is sometimes used to refer to hydrogen-richhydrocarbon molecules (as distinguished from photon flux), while alsogenerating, by condensation, heavier hydrocarbon molecules which arerelatively depleted of hydrogen. The methodology provides homolytic, orsymmetrical, breakage and produces alkenes, which may be optionallyenzymatically saturated as described above.

Catalytic and thermal methods are standard in plants for hydrocarbonprocessing and oil refining. Thus hydrocarbons produced by cells asdescribed herein can be collected and processed or refined viaconventional means. See Hillen et al. (Biotechnology and Bioengineering,Vol. XXIV: 193-205 (1982)) for a report on hydrocracking ofmicroalgae-produced hydrocarbons. In alternative embodiments, thefraction is treated with another catalyst, such as an organic compound,heat, and/or an inorganic compound. For processing of lipids intobiodiesel, a transesterification process is used as described below inthis Section.

Hydrocarbons produced via methods of the present invention are useful ina variety of industrial applications. For example, the production oflinear alkylbenzene sulfonate (LAS), an anionic surfactant used innearly all types of detergents and cleaning preparations, utilizeshydrocarbons generally comprising a chain of 10-14 carbon atoms. See,for example, U.S. Pat. Nos. 6,946,430; 5,506,201; 6,692,730; 6,268,517;6,020,509; 6,140,302; 5,080,848; and 5,567,359. Surfactants, such asLAS, can be used in the manufacture of personal care compositions anddetergents, such as those described in U.S. Pat. Nos. 5,942,479;6,086,903; 5,833,999; 6,468,955; and 6,407,044.

Increasing interest is directed to the use of hydrocarbon components ofbiological origin in fuels, such as biodiesel, renewable diesel, and jetfuel, since renewable biological starting materials that may replacestarting materials derived from fossil fuels are available, and the usethereof is desirable. There is an urgent need for methods for producinghydrocarbon components from biological materials. The present inventionfulfills this need by providing methods for production of biodiesel,renewable diesel, and jet fuel using the lipids generated by the methodsdescribed herein as a biological material to produce biodiesel,renewable diesel, and jet fuel.

Traditional diesel fuels are petroleum distillates rich in paraffinichydrocarbons. They have boiling ranges as broad as 370° to 780° F.,which are suitable for combustion in a compression ignition engine, suchas a diesel engine vehicle. The American Society of Testing andMaterials (ASTM) establishes the grade of diesel according to theboiling range, along with allowable ranges of other fuel properties,such as cetane number, cloud point, flash point, viscosity, anilinepoint, sulfur content, water content, ash content, copper stripcorrosion, and carbon residue. Technically, any hydrocarbon distillatematerial derived from biomass or otherwise that meets the appropriateASTM specification can be defined as diesel fuel (ASTM D975), jet fuel(ASTM D1655), or as biodiesel if it is a fatty acid methyl ester (ASTMD6751).

After extraction, lipid and/or hydrocarbon components recovered from themicrobial biomass described herein can be subjected to chemicaltreatment to manufacture a fuel for use in diesel vehicles and jetengines.

Biodiesel is a liquid which varies in color—between golden and darkbrown—depending on the production feedstock. It is practicallyimmiscible with water, has a high boiling point and low vapor pressure.Biodiesel refers to a diesel-equivalent processed fuel for use indiesel-engine vehicles. Biodiesel is biodegradable and non-toxic. Anadditional benefit of biodiesel over conventional diesel fuel is lowerengine wear. Typically, biodiesel comprises C14-C18 alkyl esters.Various processes convert biomass or a lipid produced and isolated asdescribed herein to diesel fuels. A preferred method to producebiodiesel is by transesterification of a lipid as described herein. Apreferred alkyl ester for use as biodiesel is a methyl ester or ethylester.

Biodiesel produced by a method described herein can be used alone orblended with conventional diesel fuel at any concentration in mostmodern diesel-engine vehicles. When blended with conventional dieselfuel (petroleum diesel), biodiesel may be present from about 0.1% toabout 99.9%. Much of the world uses a system known as the “B” factor tostate the amount of biodiesel in any fuel mix. For example, fuelcontaining 20% biodiesel is labeled B20. Pure biodiesel is referred toas B100.

Biodiesel can also be used as a heating fuel in domestic and commercialboilers. Existing oil boilers may contain rubber parts and may requireconversion to run on biodiesel. The conversion process is usuallyrelatively simple, involving the exchange of rubber parts for syntheticparts due to biodiesel being a strong solvent. Due to its strong solventpower, burning biodiesel will increase the efficiency of boilers.Biodiesel can be used as an additive in formulations of diesel toincrease the lubricity of pure Ultra-Low Sulfur Diesel (ULSD) fuel,which is advantageous because it has virtually no sulfur content.Biodiesel is a better solvent than petrodiesel and can be used to breakdown deposits of residues in the fuel lines of vehicles that havepreviously been run on petrodiesel.

Biodiesel can be produced by transesterification of triglyceridescontained in oil-rich biomass. Thus, in another aspect of the presentinvention a method for producing biodiesel is provided. In a preferredembodiment, the method for producing biodiesel comprises the steps of(a) cultivating a lipid-containing microorganism using methods disclosedherein (b) lysing a lipid-containing microorganism to produce a lysate,(c) isolating lipid from the lysed microorganism, and (d)transesterifying the lipid composition, whereby biodiesel is produced.Methods for growth of a microorganism, lysing a microorganism to producea lysate, treating the lysate in a medium comprising an organic solventto form a heterogeneous mixture and separating the treated lysate into alipid composition have been described above and can also be used in themethod of producing biodiesel.

The lipid profile of the biodiesel is usually highly similar to thelipid profile of the feedstock oil. Other oils provided by the methodsand compositions of the invention can be subjected totransesterification to yield biodiesel with lipid profiles including (a)at least 4% C8-C14; (b) at least 0.3% C8; (c) at least 2% C10; (d) atleast 2% C12; and (3) at least 30% C8-C14.

Lipid compositions can be subjected to transesterification to yieldlong-chain fatty acid esters useful as biodiesel. Preferredtransesterification reactions are outlined below and include basecatalyzed transesterification and transesterification using recombinantlipases. In a base-catalyzed transesterification process, thetriacylglycerides are reacted with an alcohol, such as methanol orethanol, in the presence of an alkaline catalyst, typically potassiumhydroxide. This reaction forms methyl or ethyl esters and glycerin(glycerol) as a byproduct.

Animal and plant oils are typically made of triglycerides which areesters of free fatty acids with the trihydric alcohol, glycerol. Intransesterification, the glycerol in a triacylglyceride (TAG) isreplaced with a short-chain alcohol such as methanol or ethanol. Atypical reaction scheme is as follows:

In this reaction, the alcohol is deprotonated with a base to make it astronger nucleophile. Commonly, ethanol or methanol is used in vastexcess (up to 50-fold). Normally, this reaction will proceed eitherexceedingly slowly or not at all. Heat, as well as an acid or base canbe used to help the reaction proceed more quickly. The acid or base arenot consumed by the transesterification reaction, thus they are notreactants but catalysts. Almost all biodiesel has been produced usingthe base-catalyzed technique as it requires only low temperatures andpressures and produces over 98% conversion yield (provided the startingoil is low in moisture and free fatty acids).

Transesterification has also been carried out, as discussed above, usingan enzyme, such as a lipase instead of a base. Lipase-catalyzedtransesterification can be carried out, for example, at a temperaturebetween the room temperature and 80° C., and a mole ratio of the TAG tothe lower alcohol of greater than 1:1, preferably about 3:1. Lipasessuitable for use in transesterification include, but are not limited to,those listed in Table 9. Other examples of lipases useful fortransesterification are found in, e.g. U.S. Pat. Nos. 4,798,793;4,940,845 5,156,963; 5,342,768; 5,776,741 and WO89/01032. Such lipasesinclude, but are not limited to, lipases produced by microorganisms ofRhizopus, Aspergillus, Candida, Mucor, Pseudomonas, Rhizomucor, Candida,and Humicola and pancreas lipase.

TABLE 9 Lipases suitable for use in transesterification. Aspergillusniger lipase ABG73614, Candida antarctica lipase B (novozym-435)CAA83122, Candida cylindracea lipase AAR24090, Candida lipolytica lipase(Lipase L; Amano Pharmaceutical Co., Ltd.), Candida rugosa lipase (e.g.,Lipase-OF; Meito Sangyo Co., Ltd.), Mucor miehei lipase (Lipozyme IM20), Pseudomonas fluorescens lipase AAA25882, Rhizopus japonicas lipase(Lilipase A-10FG) Q7M4U7_1, Rhizomucor miehei lipase B34959, Rhizopusoryzae lipase (Lipase F) AAF32408, Serratia marcescens lipase (SMEnzyme) ABI13521, Thermomyces lanuginosa lipase CAB58509, Lipase P(Nagase ChemteX Corporation), and Lipase QLM (Meito Sangyo Co., Ltd.,Nagoya, Japan)

One challenge to using a lipase for the production of fatty acid esterssuitable for biodiesel is that the price of lipase is much higher thanthe price of sodium hydroxide (NaOH) used by the strong base process.This challenge has been addressed by using an immobilized lipase, whichcan be recycled. However, the activity of the immobilized lipase must bemaintained after being recycled for a minimum number of cycles to allowa lipase-based process to compete with the strong base process in termsof the production cost. Immobilized lipases are subject to poisoning bythe lower alcohols typically used in transesterification. U.S. Pat. No.6,398,707 (issued Jun. 4, 2002 to Wu et al.) describes methods forenhancing the activity of immobilized lipases and regeneratingimmobilized lipases having reduced activity. Some suitable methodsinclude immersing an immobilized lipase in an alcohol having a carbonatom number not less than 3 for a period of time, preferably from 0.5-48hours, and more preferably from 0.5-1.5 hours. Some suitable methodsalso include washing a deactivated immobilized lipase with an alcoholhaving a carbon atom number not less than 3 and then immersing thedeactivated immobilized lipase in a vegetable oil for 0.5-48 hours.

In particular embodiments, a recombinant lipase is expressed in the samemicroorganisms that produce the lipid on which the lipase acts. Suitablerecombinant lipases include those listed above in Table 9 and/or havingGenBank Accession numbers listed above in Table 9, or a polypeptide thathas at least 70% amino acid identity with one of the lipases listedabove in Table 9 and that exhibits lipase activity. In additionalembodiments, the enzymatic activity is present in a sequence that has atleast about 75%, at least about 80%, at least about 85%, at least about90%, at least about 95%, or at least about 99% identity with one of theabove described sequences, all of which are hereby incorporated byreference as if fully set forth. DNA encoding the lipase and selectablemarker is preferably codon-optimized cDNA. Methods of recoding genes forexpression in microalgae are described in U.S. Pat. No. 7,135,290.

The common international standard for biodiesel is EN 14214. ASTM D6751is the most common biodiesel standard referenced in the United Statesand Canada. Germany uses DIN EN 14214 and the UK requires compliancewith BS EN 14214. Basic industrial tests to determine whether theproducts conform to these standards typically include gaschromatography, HPLC, and others. Biodiesel meeting the qualitystandards is very non-toxic, with a toxicity rating (LD₅₀) of greaterthan 50 mL/kg.

Although biodiesel that meets the ASTM standards has to be non-toxic,there can be contaminants which tend to crystallize and/or precipitateand fall out of solution as sediment. Sediment formation is particularlya problem when biodiesel is used at lower temperatures. The sediment orprecipitates may cause problems such as decreasing fuel flow, cloggingfuel lines, clogging filters, etc. Processes are well-known in the artthat specifically deal with the removal of these contaminants andsediments in biodiesel in order to produce a higher quality product.Examples for such processes include, but are not limited to,pretreatment of the oil to remove contaiminants such as phospholipidsand free fatty acids (e.g., degumming, caustic refining and silicaadsorbant filtration) and cold filtration. Cold filtration is a processthat was developed specifically to remove any particulates and sedimentsthat are present in the biodiesel after production. This process coolsthe biodiesel and filters out any sediments or precipitates that mightform when the fuel is used at a lower temperature. Such a process iswell known in the art and is described in US Patent ApplicationPublication No. 2007-0175091. Suitable methods may include cooling thebiodiesel to a temperature of less than about 38° C. so that theimpurities and contaminants precipitate out as particulates in thebiodiesel liquid. Diatomaceous earth or other filtering material maythen added to the cooled biodiesel to form a slurry, which may thenfiltered through a pressure leaf or other type of filter to remove theparticulates. The filtered biodiesel may then be run through a polishfilter to remove any remaining sediments and diatomaceous earth, so asto produce the final biodiesel product.

Example 9 describes the production of biodiesel using triglyceride oilfrom Prototheca moriformis. The Cold Soak Filterability by the ASTMD6751 A1 method of the biodiesel produced in Example 9 was 120 secondsfor a volume of 300 ml. This test involves filtration of 300 ml of B100,chilled to 40° F. for 16 hours, allowed to warm to room temp, andfiltered under vacuum using 0.7 micron glass fiber filter with stainlesssteel support. Oils of the invention can be transesterified to generatebiodiesel with a cold soak time of less than 120 seconds, less than 100seconds, and less than 90 seconds.

Subsequent processes may also be used if the biodiesel will be used inparticularly cold temperatures. Such processes include winterization andfractionation. Both processes are designed to improve the cold flow andwinter performance of the fuel by lowering the cloud point (thetemperature at which the biodiesel starts to crystallize). There areseveral approaches to winterizing biodiesel. One approach is to blendthe biodiesel with petroleum diesel. Another approach is to useadditives that can lower the cloud point of biodiesel. Another approachis to remove saturated methyl esters indiscriminately by mixing inadditives and allowing for the crystallization of saturates and thenfiltering out the crystals. Fractionation selectively separates methylesters into individual components or fractions, allowing for the removalor inclusion of specific methyl esters. Fractionation methods includeurea fractionation, solvent fractionation and thermal distillation.

Another valuable fuel provided by the methods of the present inventionis renewable diesel, which comprises alkanes, such as C10:0, C12:0,C14:0, C16:0 and C18:0 and thus, are distinguishable from biodiesel.High quality renewable diesel conforms to the ASTM D975 standard. Thelipids produced by the methods of the present invention can serve asfeedstock to produce renewable diesel. Thus, in another aspect of thepresent invention, a method for producing renewable diesel is provided.Renewable diesel can be produced by at least three processes:hydrothermal processing (hydrotreating); hydroprocessing; and indirectliquefaction. These processes yield non-ester distillates. During theseprocesses, triacylglycerides produced and isolated as described herein,are converted to alkanes.

In one embodiment, the method for producing renewable diesel comprises(a) cultivating a lipid-containing microorganism using methods disclosedherein (b) lysing the microorganism to produce a lysate, (c) isolatinglipid from the lysed microorganism, and (d) deoxygenating andhydrotreating the lipid to produce an alkane, whereby renewable dieselis produced. Lipids suitable for manufacturing renewable diesel can beobtained via extraction from microbial biomass using an organic solventsuch as hexane, or via other methods, such as those described in U.S.Pat. No. 5,928,696. Some suitable methods may include mechanicalpressing and centrifuging.

In some methods, the microbial lipid is first cracked in conjunctionwith hydrotreating to reduce carbon chain length and saturate doublebonds, respectively. The material is then isomerized, also inconjunction with hydrotreating. The naptha fraction can then be removedthrough distillation, followed by additional distillation to vaporizeand distill components desired in the diesel fuel to meet an ASTM D975standard while leaving components that are heavier than desired formeeting the D975 standard. Hydrotreating, hydrocracking, deoxygenationand isomerization methods of chemically modifying oils, includingtriglyceride oils, are well known in the art. See for example Europeanpatent applications EP1741768 (A1); EP1741767 (A1); EP1682466 (A1);EP1640437 (A1); EP1681337 (A1); EP1795576 (A1); and U.S. Pat. Nos.7,238,277; 6,630,066; 6,596,155; 6,977,322; 7,041,866; 6,217,746;5,885,440; 6,881,873.

In one embodiment of the method for producing renewable diesel, treatingthe lipid to produce an alkane is performed by hydrotreating of thelipid composition. In hydrothermal processing, typically, biomass isreacted in water at an elevated temperature and pressure to form oilsand residual solids. Conversion temperatures are typically 300° to 660°F., with pressure sufficient to keep the water primarily as a liquid,100 to 170 standard atmosphere (atm). Reaction times are on the order of15 to 30 minutes. After the reaction is completed, the organics areseparated from the water. Thereby a distillate suitable for diesel isproduced.

In some methods of making renewable diesel, the first step of treating atriglyceride is hydroprocessing to saturate double bonds, followed bydeoxygenation at elevated temperature in the presence of hydrogen and acatalyst. In some methods, hydrogenation and deoxygenation occur in thesame reaction. In other methods deoxygenation occurs beforehydrogenation. Isomerization is then optionally performed, also in thepresence of hydrogen and a catalyst. Naphtha components are preferablyremoved through distillation. For examples, see U.S. Pat. No. 5,475,160(hydrogenation of triglycerides); U.S. Pat. No. 5,091,116(deoxygenation, hydrogenation and gas removal); U.S. Pat. No. 6,391,815(hydrogenation); and U.S. Pat. No. 5,888,947 (isomerization).

One suitable method for the hydrogenation of triglycerides includespreparing an aqueous solution of copper, zinc, magnesium and lanthanumsalts and another solution of alkali metal or preferably, ammoniumcarbonate. The two solutions may be heated to a temperature of about 20°C. to about 85° C. and metered together into a precipitation containerat rates such that the pH in the precipitation container is maintainedbetween 5.5 and 7.5 in order to form a catalyst. Additional water may beused either initially in the precipitation container or addedconcurrently with the salt solution and precipitation solution. Theresulting precipitate may then be thoroughly washed, dried, calcined atabout 300° C. and activated in hydrogen at temperatures ranging fromabout 100° C. to about 400° C. One or more triglycerides may then becontacted and reacted with hydrogen in the presence of theabove-described catalyst in a reactor. The reactor may be a trickle bedreactor, fixed bed gas-solid reactor, packed bubble column reactor,continuously stirred tank reactor, a slurry phase reactor, or any othersuitable reactor type known in the art. The process may be carried outeither batchwise or in continuous fashion. Reaction temperatures aretypically in the range of from about 170° C. to about 250° C. whilereaction pressures are typically in the range of from about 300 psig toabout 2000 psig. Moreover, the molar ratio of hydrogen to triglyceridein the process of the present invention is typically in the range offrom about 20:1 to about 700:1. The process is typically carried out ata weight hourly space velocity (WHSV) in the range of from about 0.1 hr¹to about 5 hr¹. One skilled in the art will recognize that the timeperiod required for reaction will vary according to the temperatureused, the molar ratio of hydrogen to triglyceride, and the partialpressure of hydrogen. The products produced by the such hydrogenationprocesses include fatty alcohols, glycerol, traces of paraffins andunreacted triglycerides. These products are typically separated byconventional means such as, for example, distillation, extraction,filtration, crystallization, and the like.

Petroleum refiners use hydroprocessing to remove impurities by treatingfeeds with hydrogen. Hydroprocessing conversion temperatures aretypically 300° to 700° F. Pressures are typically 40 to 100 atm. Thereaction times are typically on the order of 10 to 60 minutes. Solidcatalysts are employed to increase certain reaction rates, improveselectivity for certain products, and optimize hydrogen consumption.

Suitable methods for the deoxygenation of an oil includes heating an oilto a temperature in the range of from about 350° F. to about 550° F. andcontinuously contacting the heated oil with nitrogen under at leastpressure ranging from about atmospeheric to above for at least about 5minutes.

Suitable methods for isomerization include using alkali isomerizationand other oil isomerization known in the art.

Hydrotreating and hydroprocessing ultimately lead to a reduction in themolecular weight of the triglyceride feed. The triglyceride molecule isreduced to four hydrocarbon molecules under hydroprocessing conditions:a propane molecule and three heavier hydrocarbon molecules, typically inthe C8 to C18 range.

Thus, in one embodiment, the product of one or more chemical reaction(s)performed on lipid compositions of the invention is an alkane mixturethat comprises ASTM D975 renewable diesel. Production of hydrocarbons bymicroorganisms is reviewed by Metzger et al. Appl Microbiol Biotechnol(2005) 66: 486-496 and A Look Back at the U.S. Department of Energy'sAquatic Species Program: Biodiesel from Algae, NREL/TP-580-24190, JohnSheehan, Terri Dunahay, John Benemann and Paul Roessler (1998).

The distillation properties of a diesel fuel is described in terms ofT10-T90 (temperature at 10% and 90%, respectively, volume distilled).Renewable diesel was produced from Prototheca moriformis triglycerideoil and is described in Example 9. The T10-T90 of the material producedin Example 9 was 57.9° C. Methods of hydrotreating, isomerization, andother covalent modification of oils disclosed herein, as well as methodsof distillation and fractionation (such as cold filtration) disclosedherein, can be employed to generate renewable diesel compositions withother T10-T90 ranges, such as 20, 25, 30, 35, 40, 45, 50, 60 and 65° C.using triglyceride oils produced according to the methods disclosedherein.

The T10 of the material produced in Example 9 was 242.1° C. Methods ofhydrotreating, isomerization, and other covalent modification of oilsdisclosed herein, as well as methods of distillation and fractionation(such as cold filtration) disclosed herein, can be employed to generaterenewable diesel compositions with other T10 values, such as T10 between180 and 295, between 190 and 270, between 210 and 250, between 225 and245, and at least 290.

The T90 of the material produced in Example 9 was 300° C. Methods ofhydrotreating, isomerization, and other covalent modification of oilsdisclosed herein, as well as methods of distillation and fractionation(such as cold filtration) disclosed herein can be employed to generaterenewable diesel compositions with other T90 values, such as T90 between280 and 380, between 290 and 360, between 300 and 350, between 310 and340, and at least 290.

The FBP of the material produced in Example 9 was 300° C. Methods ofhydrotreating, isomerization, and other covalent modification of oilsdisclosed herein, as well as methods of distillation and fractionation(such as cold filtration) disclosed herein, can be employed to generaterenewable diesel compositions with other FBP values, such as FBP between290 and 400, between 300 and 385, between 310 and 370, between 315 and360, and at least 300.

Other oils provided by the methods and compositions of the invention canbe subjected to combinations of hydrotreating, isomerization, and othercovalent modification including oils with lipid profiles including (a)at least 4% C8-C14; (b) at least 0.3% C8; (c) at least 2% C10; (d) atleast 2% C12; and (3) at least 30% C8-C14.

A traditional ultra-low sulfur diesel can be produced from any form ofbiomass by a two-step process. First, the biomass is converted to asyngas, a gaseous mixture rich in hydrogen and carbon monoxide. Then,the syngas is catalytically converted to liquids. Typically, theproduction of liquids is accomplished using Fischer-Tropsch (FT)synthesis. This technology applies to coal, natural gas, and heavy oils.Thus, in yet another preferred embodiment of the method for producingrenewable diesel, treating the lipid composition to produce an alkane isperformed by indirect liquefaction of the lipid composition.

The present invention also provides methods to produce jet fuel. Jetfuel is clear to straw colored. The most common fuel is anunleaded/paraffin oil-based fuel classified as Aeroplane A-1, which isproduced to an internationally standardized set of specifications. Jetfuel is a mixture of a large number of different hydrocarbons, possiblyas many as a thousand or more. The range of their sizes (molecularweights or carbon numbers) is restricted by the requirements for theproduct, for example, freezing point or smoke point. Kerosone-typeAeroplane fuel (including Jet A and Jet A-1) has a carbon numberdistribution between about 8 and 16 carbon numbers. Wide-cut ornaphta-type Aeroplane fuel (including Jet B) typically has a carbonnumber distribution between about 5 and 15 carbons.

Both Aeroplanes (Jet A and Jet B) may contain a number of additives.Useful additives include, but are not limited to, antioxidants,antistatic agents, corrosion inhibitors, and fuel system icing inhibitor(FSII) agents. Antioxidants prevent gumming and usually, are based onalkylated phenols, for example, AO-30, AO-31, or AO-37. Antistaticagents dissipate static electricity and prevent sparking. Stadis 450with dinonylnaphthylsulfonic acid (DINNSA) as the active ingredient, isan example. Corrosion inhibitors, e.g., DCI-4A is used for civilian andmilitary fuels and DCI-6A is used for military fuels. FSII agents,include, e.g., Di-EGME.

In one embodiment of the invention, a jet fuel is produced by blendingalgal fuels with existing jet fuel. The lipids produced by the methodsof the present invention can serve as feedstock to produce jet fuel.Thus, in another aspect of the present invention, a method for producingjet fuel is provided. Herewith two methods for producing jet fuel fromthe lipids produced by the methods of the present invention areprovided: fluid catalytic cracking (FCC); and hydrodeoxygenation (HDO).

Fluid Catalytic Cracking (FCC) is one method which is used to produceolefins, especially propylene from heavy crude fractions. The lipidsproduced by the method of the present invention can be converted toolefins. The process involves flowing the lipids produced through an FCCzone and collecting a product stream comprised of olefins, which isuseful as a jet fuel. The lipids produced are contacted with a crackingcatalyst at cracking conditions to provide a product stream comprisingolefins and hydrocarbons useful as jet fuel.

In one embodiment, the method for producing jet fuel comprises (a)cultivating a lipid-containing microorganism using methods disclosedherein, (b) lysing the lipid-containing microorganism to produce alysate, (c) isolating lipid from the lysate, and (d) treating the lipidcomposition, whereby jet fuel is produced. In one embodiment of themethod for producing a jet fuel, the lipid composition can be flowedthrough a fluid catalytic cracking zone, which, in one embodiment, maycomprise contacting the lipid composition with a cracking catalyst atcracking conditions to provide a product stream comprising C₂-C₅olefins.

In certain embodiments of this method, it may be desirable to remove anycontaminants that may be present in the lipid composition. Thus, priorto flowing the lipid composition through a fluid catalytic crackingzone, the lipid composition is pretreated. Pretreatment may involvecontacting the lipid composition with an ion-exchange resin. The ionexchange resin is an acidic ion exchange resin, such as Amberlyst™-15and can be used as a bed in a reactor through which the lipidcomposition is flowed, either upflow or downflow. Other pretreatmentsmay include mild acid washes by contacting the lipid composition with anacid, such as sulfuric, acetic, nitric, or hydrochloric acid. Contactingis done with a dilute acid solution usually at ambient temperature andatmospheric pressure.

The lipid composition, optionally pretreated, is flowed to an FCC zonewhere the hydrocarbonaceous components are cracked to olefins. Catalyticcracking is accomplished by contacting the lipid composition in areaction zone with a catalyst composed of finely divided particulatematerial. The reaction is catalytic cracking, as opposed tohydrocracking, and is carried out in the absence of added hydrogen orthe consumption of hydrogen. As the cracking reaction proceeds,substantial amounts of coke are deposited on the catalyst. The catalystis regenerated at high temperatures by burning coke from the catalyst ina regeneration zone. Coke-containing catalyst, referred to herein as“coked catalyst”, is continually transported from the reaction zone tothe regeneration zone to be regenerated and replaced by essentiallycoke-free regenerated catalyst from the regeneration zone. Fluidizationof the catalyst particles by various gaseous streams allows thetransport of catalyst between the reaction zone and regeneration zone.Methods for cracking hydrocarbons, such as those of the lipidcomposition described herein, in a fluidized stream of catalyst,transporting catalyst between reaction and regeneration zones, andcombusting coke in the regenerator are well known by those skilled inthe art of FCC processes. Exemplary FCC applications and catalystsuseful for cracking the lipid composition to produce C₂-C₅ olefins aredescribed in U.S. Pat. Nos. 6,538,169, 7,288,685, which are incorporatedin their entirety by reference.

Suitable FCC catalysts generally comprise at least two components thatmay or may not be on the same matrix. In some embodiments, both twocomponents may be circulated throughout the entire reaction vessel. Thefirst component generally includes any of the well-known catalysts thatare used in the art of fluidized catalytic cracking, such as an activeamorphous clay-type catalyst and/or a high activity, crystallinemolecular sieve. Molecular sieve catalysts may be preferred overamorphous catalysts because of their much-improved selectivity todesired products. IN some preferred embodiments, zeolites may be used asthe molecular sieve in the FCC processes. Preferably, the first catalystcomponent comprises a large pore zeolite, such as an Y-type zeolite, anactive alumina material, a binder material, comprising either silica oralumina and an inert filler such as kaolin.

In one embodiment, cracking the lipid composition of the presentinvention, takes place in the riser section or, alternatively, the liftsection, of the FCC zone. The lipid composition is introduced into theriser by a nozzle resulting in the rapid vaporization of the lipidcomposition. Before contacting the catalyst, the lipid composition willordinarily have a temperature of about 149° C. to about 316° C. (300° F.to 600° F.). The catalyst is flowed from a blending vessel to the riserwhere it contacts the lipid composition for a time of abort 2 seconds orless.

The blended catalyst and reacted lipid composition vapors are thendischarged from the top of the riser through an outlet and separatedinto a cracked product vapor stream including olefins and a collectionof catalyst particles covered with substantial quantities of coke andgenerally referred to as “coked catalyst.” In an effort to minimize thecontact time of the lipid composition and the catalyst which may promotefurther conversion of desired products to undesirable other products,any arrangement of separators such as a swirl arm arrangement can beused to remove coked catalyst from the product stream quickly. Theseparator, e.g. swirl arm separator, is located in an upper portion of achamber with a stripping zone situated in the lower portion of thechamber. Catalyst separated by the swirl arm arrangement drops down intothe stripping zone. The cracked product vapor stream comprising crackedhydrocarbons including light olefins and some catalyst exit the chambervia a conduit which is in communication with cyclones. The cyclonesremove remaining catalyst particles from the product vapor stream toreduce particle concentrations to very low levels. The product vaporstream then exits the top of the separating vessel. Catalyst separatedby the cyclones is returned to the separating vessel and then to thestripping zone. The stripping zone removes adsorbed hydrocarbons fromthe surface of the catalyst by counter-current contact with steam.

Low hydrocarbon partial pressure operates to favor the production oflight olefins. Accordingly, the riser pressure is set at about 172 to241 kPa (25 to 35 psia) with a hydrocarbon partial pressure of about 35to 172 kPa (5 to 25 psia), with a preferred hydrocarbon partial pressureof about 69 to 138 kPa (10 to 20 psia). This relatively low partialpressure for hydrocarbon is achieved by using steam as a diluent to theextent that the diluent is 10 to 55 wt-% of lipid composition andpreferably about 15 wt-% of lipid composition. Other diluents such asdry gas can be used to reach equivalent hydrocarbon partial pressures.

The temperature of the cracked stream at the riser outlet will be about510° C. to 621° C. (950° F. to 1150° F.). However, riser outlettemperatures above 566° C. (1050° F.) make more dry gas and moreolefins. Whereas, riser outlet temperatures below 566° C. (1050° F.)make less ethylene and propylene. Accordingly, it is preferred to runthe FCC process at a preferred temperature of about 566° C. to about630° C., preferred pressure of about 138 kPa to about 240 kPa (20 to 35psia). Another condition for the process is the catalyst to lipidcomposition ratio which can vary from about 5 to about 20 and preferablyfrom about 10 to about 15.

In one embodiment of the method for producing a jet fuel, the lipidcomposition is introduced into the lift section of an FCC reactor. Thetemperature in the lift section will be very hot and range from about700° C. (1292° F.) to about 760° C. (1400° F.) with a catalyst to lipidcomposition ratio of about 100 to about 150. It is anticipated thatintroducing the lipid composition into the lift section will produceconsiderable amounts of propylene and ethylene.

In another embodiment of the method for producing a jet fuel using thelipid composition or the lipids produced as described herein, thestructure of the lipid composition or the lipids is broken by a processreferred to as hydrodeoxygenation (HDO). HDO means removal of oxygen bymeans of hydrogen, that is, oxygen is removed while breaking thestructure of the material. Olefinic double bonds are hydrogenated andany sulphur and nitrogen compounds are removed. Sulphur removal iscalled hydrodesulphurization (HDS). Pretreatment and purity of the rawmaterials (lipid composition or the lipids) contribute to the servicelife of the catalyst.

Generally in the HDO/HDS step, hydrogen is mixed with the feed stock(lipid composition or the lipids) and then the mixture is passed througha catalyst bed as a co-current flow, either as a single phase or a twophase feed stock. After the HDO/MDS step, the product fraction isseparated and passed to a separate isomerzation reactor. Anisomerization reactor for biological starting material is described inthe literature (FI 100 248) as a co-current reactor.

The process for producing a fuel by hydrogenating a hydrocarbon feed,e.g., the lipid composition or the lipids herein, can also be performedby passing the lipid composition or the lipids as a co-current flow withhydrogen gas through a first hydrogenation zone, and thereafter thehydrocarbon effluent is further hydrogenated in a second hydrogenationzone by passing hydrogen gas to the second hydrogenation zone as acounter-current flow relative to the hydrocarbon effluent. Exemplary HDOapplications and catalysts useful for cracking the lipid composition toproduce C₂-C₅ olefins are described in U.S. Pat. No. 7,232,935, which isincorporated in its entirety by reference.

Typically, in the hydrodeoxygenation step, the structure of thebiological component, such as the lipid composition or lipids herein, isdecomposed, oxygen, nitrogen, phosphorus and sulphur compounds, andlight hydrocarbons as gas are removed, and the olefinic bonds arehydrogenated. In the second step of the process, i.e. in the so-calledisomerization step, isomerzation is carried out for branching thehydrocarbon chain and improving the performance of the paraffin at lowtemperatures.

In the first step, i.e. HDO step, of the cracking process, hydrogen gasand the lipid composition or lipids herein which are to be hydrogenatedare passed to a HDO catalyst bed system either as co-current orcounter-current flows, said catalyst bed system comprising one or morecatalyst bed(s), preferably 1-3 catalyst beds. The HDO step is typicallyoperated in a co-current manner. In case of a HDO catalyst bed systemcomprising two or more catalyst beds, one or more of the beds may beoperated using the counter-current flow principle. In the HDO step, thepressure varies between 20 and 150 bar, preferably between 50 and 100bar, and the temperature varies between 200 and 500° C., preferably inthe range of 300−400° C. In the HDO step, known hydrogenation catalystscontaining metals from Group VII and/or VIB of the Periodic System maybe used. Preferably, the hydrogenation catalysts are supported Pd, Pt,Ni, NiMo or a CoMo catalysts, the support being alumina and/or silica.Typically, NiMo/Al₂O₃ and CoMo/Al₂O₃ catalysts are used.

Prior to the HDO step, the lipid composition or lipids herein mayoptionally be treated by prehydrogenation under milder conditions thusavoiding side reactions of the double bonds. Such prehydrogenation iscarried out in the presence of a prehydrogenation catalyst attemperatures of 50-400° C. and at hydrogen pressures of 1-200 bar,preferably at a temperature between 150 and 250° C. and at a hydrogenpressure between 10 and 100 bar. The catalyst may contain metals fromGroup VIII and/or VIB of the Periodic System. Preferably, theprehydrogenation catalyst is a supported Pd, Pt, Ni, NiMo or a CoMocatalyst, the support being alumina and/or silica.

A gaseous stream from the HDO step containing hydrogen is cooled andthen carbon monoxide, carbon dioxide, nitrogen, phosphorus and sulphurcompounds, gaseous light hydrocarbons and other impurities are removedtherefrom. After compressing, the purified hydrogen or recycled hydrogenis returned back to the first catalyst bed and/or between the catalystbeds to make up for the withdrawn gas stream. Water is removed from thecondensed liquid. The liquid is passed to the first catalyst bed orbetween the catalyst beds.

After the HDO step, the product is subjected to an isomerization step.It is substantial for the process that the impurities are removed ascompletely as possible before the hydrocarbons are contacted with theisomerization catalyst. The isomerization step comprises an optionalstripping step, wherein the reaction product from the HDO step may bepurified by stripping with water vapour or a suitable gas such as lighthydrocarbon, nitrogen or hydrogen. The optional stripping step iscarried out in counter-current manner in a unit upstream of theisomerization catalyst, wherein the gas and liquid are contacted witheach other, or before the actual isomerization reactor in a separatestripping unit utilizing counter-current principle.

After the stripping step the hydrogen gas and the hydrogenated lipidcomposition or lipids herein, and optionally an n-paraffin mixture, arepassed to a reactive isomerization unit comprising one or severalcatalyst bed(s). The catalyst beds of the isomerization step may operateeither in co-current or counter-current manner.

It is important for the process that the counter-current flow principleis applied in the isomerization step. In the isomerization step this isdone by carrying out either the optional stripping step or theisomerization reaction step or both in counter-current manner. In theisomerzation step, the pressure varies in the range of 20-150 bar,preferably in the range of 20-100 bar, the temperature being between 200and 500° C., preferably between 300 and 400° C. In the isomerizationstep, isomerization catalysts known in the art may be used. Suitableisomerization catalysts contain molecular sieve and/or a metal fromGroup VII and/or a carrier. Preferably, the isomerization catalystcontains SAPO-11 or SAPO41 or ZSM-22 or ZSM-23 or ferrierite and Pt, Pdor Ni and Al₂O₃ or SiO₂. Typical isomerization catalysts are, forexample, Pt/SAPO-11/Al₂O₃, Pt/ZSM-22/Al₂O₃, Pt/ZSM-23/Al₂O₃ andPt/SAPO-11/SiO₂. The isomerization step and the HDO step may be carriedout in the same pressure vessel or in separate pressure vessels.Optional prehydrogenation may be carried out in a separate pressurevessel or in the same pressure vessel as the HDO and isomerizationsteps.

Thus, in one embodiment, the product of one or more chemical reactionsis an alkane mixture that comprises HRJ-5. In another embodiment, theproduct of the one or more chemical reactions is an alkane mixture thatcomprises ASTM D1655 jet fuel. In some embodiments, the compositioncomforming to the specification of ASTM 1655 jet fuel has a sulfurcontent that is less than 10 ppm. In other embodiments, the compositionconforming to the specification of ASTM 1655 jet fuel has a T10 value ofthe distillation curve of less than 205° C. In another embodiment, thecomposition conforming to the specification of ASTM 1655 jet fuel has afinal boiling point (FBP) of less than 300° C. In another embodiment,the composition conforming to the specification of ASTM 1655 jet fuelhas a flash point of at least 38° C. In another embodiment, thecomposition conforming to the specification of ASTM 1655 jet fuel has adensity between 775K/M³ and 840K/M³. In yet another embodiment, thecomposition conforming to the specification of ASTM 1655 jet fuel has afreezing point that is below −47° C. In another embodiment, thecomposition conforming to the specification of ASTM 1655 jet fuel has anet Heat of Combustion that is at least 42.8 MJ/K. In anotherembodiment, the composition conforming to the specification of ASTM 1655jet fuel has a hydrogen content that is at least 13.4 mass %. In anotherembodiment, the composition conforming to the specification of ASTM 1655jet fuel has a thermal stability, as tested by quantitative gravimetricJFTOT at 260° C., that is below 3 mm of Hg. In another embodiment, thecomposition conforming to the specification of ASTM 1655 jet fuel has anexistent gum that is below 7 mg/dl.

Thus, the present invention discloses a variety of methods in whichchemical modification of microalgal lipid is undertaken to yieldproducts useful in a variety of industrial and other applications.Examples of processes for modifying oil produced by the methodsdisclosed herein include, but are not limited to, hydrolysis of the oil,hydroprocessing of the oil, and esterification of the oil. Otherchemical modification of microalgal lipid include, without limitation,epoxidation, oxidation, hydrolysis, sulfations, sulfonation,ethoxylation, propoxylation, amidation, and saponification. Themodification of the microalgal oil produces basic oleochemicals that canbe further modified into selected derivative oleochemicals for a desiredfunction. In a manner similar to that described above with reference tofuel producing processes, these chemical modifications can also beperformed on oils generated from the microbial cultures describedherein. Examples of basic oleochemicals include, but are not limited to,soaps, fatty acids, fatty esters, fatty alcohols, fatty nitrogencompounds, fatty acid methyl esters, and glycerol. Examples ofderivative oleochemicals include, but are not limited to, fattynitriles, esters, dimer acids, quats, surfactants, fatty alkanolamides,fatty alcohol sulfates, resins, emulsifiers, fatty alcohols, olefins,drilling muds, polyols, polyurethanes, polyacrylates, rubber, candles,cosmetics, metallic soaps, soaps, alpha-sulphonated methyl esters, fattyalcohol sulfates, fatty alcohol ethoxylates, fatty alcohol ethersulfates, imidazolines, surfactants, detergents, esters, quats,ozonolysis products, fatty amines, fatty alkanolamides, ethoxysulfates,monoglycerides, diglycerides, triglycerides (including medium chaintriglycerides), lubricants, hydraulic fluids, greases, dielectricfluids, mold release agents, metal working fluids, heat transfer fluids,other functional fluids, industrial chemicals (e.g., cleaners, textileprocessing aids, plasticizers, stabilizers, additives), surfacecoatings, paints and lacquers, electrical wiring insulation, and higheralkanes.

Hydrolysis of the fatty acid constituents from the glycerolipidsproduced by the methods of the invention yields free fatty acids thatcan be derivatized to produce other useful chemicals. Hydrolysis occursin the presence of water and a catalyst which may be either an acid or abase. The liberated free fatty acids can be derivatized to yield avariety of products, as reported in the following: U.S. Pat. No.5,304,664 (Highly sulfated fatty acids); U.S. Pat. No. 7,262,158(Cleansing compositions); U.S. Pat. No. 7,115,173 (Fabric softenercompositions); U.S. Pat. No. 6,342,208 (Emulsions for treating skin);U.S. Pat. No. 7,264,886 (Water repellant compositions); U.S. Pat. No.6,924,333 (Paint additives); U.S. Pat. No. 6,596,768 (Lipid-enrichedruminant feedstock); and U.S. Pat. No. 6,380,410 (Surfactants fordetergents and cleaners).

With regard to hydrolysis, in one embodiment of the invention, atriglyceride oil is optionally first hydrolyzed in a liquid medium suchas water or sodium hydroxide so as to obtain glycerol and soaps. Thereare various suitable triglyceride hydrolysis methods, including, but notlimited to, saponification, acid hydrolysis, alkaline hydrolysis,enzymatic hydrolysis (referred herein as splitting), and hydrolysisusing hot-compressed water. One skilled in the art will recognize that atriglyceride oil need not be hydrolyzed in order to produce anoleochemical; rather, the oil may be converted directly to the desiredoleochemical by other known process. For example, the triglyceride oilmay be directly converted to a methyl ester fatty acid throughesterification.

In some embodiments, catalytic hydrolysis of the oil produced by methodsdisclosed herein occurs by splitting the oil into glycerol and fattyacids. As discussed above, the fatty acids may then be further processedthrough several other modifications to obtained derivativeoleochemicals. For example, in one embodiment the fatty acids mayundergo an amination reaction to produce fatty nitrogen compounds. Inanother embodiment, the fatty acids may undergo ozonolysis to producemono- and dibasic-acids.

In other embodiments hydrolysis may occur via the, splitting of oilsproduced herein to create oleochemicals. In some preferred embodimentsof the invention, a triglyceride oil may be split before other processesis performed. One skilled in the art will recognize that there are manysuitable triglyceride splitting methods, including, but not limited to,enzymatic splitting and pressure splitting.

Generally, enzymatic oil splitting methods use enzymes, lipases, asbiocatalysts acting on a water/oil mixture. Enzymatic splitting thensplits the oil or fat, respectively, is into glycerol and free fattyacids. The glycerol may then migrates into the water phase whereas theorganic phase enriches with free fatty acids.

The enzymatic splitting reactions generally take place at the phaseboundary between organic and aqueous phase, where the enzyme is presentonly at the phase boundary. Triglycerides that meet the phase boundarythen contribute to or participate in the splitting reaction. As thereaction proceeds, the occupation density or concentration of fattyacids still chemically bonded as glycerides, in comparison to free fattyacids, decreases at the phase boundary so that the reaction is sloweddown. In certain embodiments, enzymatic splitting may occur at roomtemperature. One of ordinary skill in the art would know the suitableconditions for splitting oil into the desired fatty acids.

By way of example, the reaction speed can be accelerated by increasingthe interface boundary surface. Once the reaction is complete, freefatty acids are then separated from the organic phase freed from enzyme,and the residue which still contains fatty acids chemically bonded asglycerides is fed back or recycled and mixed with fresh oil or fat to besubjected to splitting. In this manner, recycled glycerides are thensubjected to a further enzymatic splitting process. In some embodiments,the free fatty acids are extracted from an oil or fat partially split insuch a manner. In that way, if the chemically bound fatty acids(triglycerides) are returned or fed back into the splitting process, theenzyme consumption can be drastically reduced.

The splitting degree is determined as the ratio of the measured acidvalue divided by the theoretically possible acid value which can becomputed for a given oil or fat. Preferably, the acid value is measuredby means of titration according to standard common methods.Alternatively, the density of the aqueous glycerol phase can be taken asa measure for the splitting degree.

In one embodiment, the slitting process as described herein is alsosuitable for splitting the mono-, di- and triglyceride that arecontained in the so-called soap-stock from the alkali refining processesof the produced oils. In this manner, the soap-stock can bequantitatively converted without prior saponification of the neutraloils into the fatty acids. For this purpose, the fatty acids beingchemically bonded in the soaps are released, preferably beforesplitting, through an addition of acid. In certain embodiments, a buffersolution is used in addition to water and enzyme for the splittingprocess.

In one embodiment, oils produced in accordance with the methods of theinvention can also be subjected to saponification as a method ofhydrolysis. Animal and plant oils are typically made of triacylglycerols(TAGs), which are esters of fatty acids with the trihydric alcohol,glycerol. In an alkaline hydrolysis reaction, the glycerol in a TAG isremoved, leaving three carboxylic acid anions that can associate withalkali metal cations such as sodium or potassium to produce fatty acidsalts. In this scheme, the carboxylic acid constituents are cleaved fromthe glycerol moiety and replaced with hydroxyl groups. The quantity ofbase (e.g., KOH) that is used in the reaction is determined by thedesired degree of saponification. If the objective is, for example, toproduce a soap product that comprises some of the oils originallypresent in the TAG composition, an amount of base insufficient toconvert all of the TAGs to fatty acid salts is introduced into thereaction mixture. Normally, this reaction is performed in an aqueoussolution and proceeds slowly, but may be expedited by the addition ofheat. Precipitation of the fatty acid salts can be facilitated byaddition of salts, such as water-soluble alkali metal halides (e.g.,NaCl or KCl), to the reaction mixture. Preferably, the base is an alkalimetal hydroxide, such as NaOH or KOH. Alternatively, other bases, suchas alkanolamines, including for example triethanolamine andaminomethylpropanol, can be used in the reaction scheme. In some cases,these alternatives may be preferred to produce a clear soap product. Inone embodiment the lipid composition subjected to saponification is atallow mimetic (i.e., lipid composition similar to that of tallow)produced as described herein, or a blend of a tallow mimetic withanother triglyceride oil.

In some methods, the first step of chemical modification may behydroprocessing to saturate double bonds, followed by deoxygenation atelevated temperature in the presence of hydrogen and a catalyst. Inother methods, hydrogenation and deoxygenation may occur in the samereaction. In still other methods deoxygenation occurs beforehydrogenation. Isomerization may then be optionally performed, also inthe presence of hydrogen and a catalyst. Finally, gases and naphthacomponents can be removed if desired. For example, see U.S. Pat. No.5,475,160 (hydrogenation of triglycerides); U.S. Pat. No. 5,091,116(deoxygenation, hydrogenation and gas removal); U.S. Pat. No. 6,391,815(hydrogenation); and U.S. Pat. No. 5,888,947 (isomerization).

In some embodiments of the invention, the triglyceride oils arepartially or completely deoxygenated. The deoxygenation reactions formdesired products, including, but not limited to, fatty acids, fattyalcohols, polyols, ketones, and aldehydes. In general, without beinglimited by any particular theory, the deoxygenation reactions involve acombination of various different reaction pathways, including withoutlimitation: hydrogenolysis, hydrogenation, consecutivehydrogenation-hydrogenolysis, consecutive hydrogenolysis-hydrogenation,and combined hydrogenation-hydrogenolysis reactions, resulting in atleast the partial removal of oxygen from the fatty acid or fatty acidester to produce reaction products, such as fatty alcohols, that can beeasily converted to the desired chemicals by further processing. Forexample, in one embodiment, a fatty alcohol may be converted to olefinsthrough FCC reaction or to higher alkanes through a condensationreaction.

One such chemical modification is hydrogenation, which is the additionof hydrogen to double bonds in the fatty acid constituents ofglycerolipids or of free fatty acids. The hydrogenation process permitsthe transformation of liquid oils into semi-solid or solid fats, whichmay be more suitable for specific applications.

Hydrogenation of oil produced by the methods described herein can beperformed in conjunction with one or more of the methods and/ormaterials provided herein, as reported in the following: U.S. Pat. No.7,288,278 (Food additives or medicaments); U.S. Pat. No. 5,346,724(Lubrication products); U.S. Pat. No. 5,475,160 (Fatty alcohols); U.S.Pat. No. 5,091,116 (Edible oils); U.S. Pat. No. 6,808,737 (Structuralfats for margarine and spreads); U.S. Pat. No. 5,298,637(Reduced-calorie fat substitutes); U.S. Pat. No. 6,391,815(Hydrogenation catalyst and sulfur adsorbent); U.S. Pat. Nos. 5,233,099and 5,233,100 (Fatty alcohols); U.S. Pat. No. 4,584,139 (Hydrogenationcatalysts); U.S. Pat. No. 6,057,375 (Foam suppressing agents); and U.S.Pat. No. 7,118,773 (Edible emulsion spreads).

One skilled in the art will recognize that various processes may be usedto hydrogenate carbohydrates. One suitable method includes contactingthe carbohydrate with hydrogen or hydrogen mixed with a suitable gas anda catalyst under conditions sufficient in a hydrogenation reactor toform a hydrogenated product. The hydrogenation catalyst generally caninclude Cu, Re, Ni, Fe, Co, Ru, Pd, Rh, Pt, Os, Ir, and alloys or anycombination thereof, either alone or with promoters such as W, Mo, Au,Ag, Cr, Zn, Mn, Sn, B, P, Bi, and alloys or any combination thereof.Other effective hydrogenation catalyst materials include eithersupported nickel or ruthenium modified with rhenium. In an embodiment,the hydrogenation catalyst also includes any one of the supports,depending on the desired functionality of the catalyst. Thehydrogenation catalysts may be prepared by methods known to those ofordinary skill in the art.

In some embodiments the hydrogenation catalyst includes a supportedGroup VIII metal catalyst and a metal sponge material (e.g., a spongenickel catalyst). Raney nickel provides an example of an activatedsponge nickel catalyst suitable for use in this invention. In otherembodiment, the hydrogenation reaction in the invention is performedusing a catalyst comprising a nickel-rhenium catalyst or atungsten-modified nickel catalyst. One example of a suitable catalystfor the hydrogenation reaction of the invention is a carbon-supportednickel-rhenium catalyst.

In an embodiment, a suitable Raney nickel catalyst may be prepared bytreating an alloy of approximately equal amounts by weight of nickel andaluminum with an aqueous alkali solution, e.g., containing about 25weight % of sodium hydroxide. The aluminum is selectively dissolved bythe aqueous alkali solution resulting in a sponge shaped materialcomprising mostly nickel with minor amounts of aluminum. The initialalloy includes promoter metals (i.e., molybdenum or chromium) in theamount such that about 1 to 2 weight % remains in the formed spongenickel catalyst. In another embodiment, the hydrogenation catalyst isprepared using a solution of ruthenium(III) nitrosylnitrate, ruthenium(III) chloride in water to impregnate a suitable support material. Thesolution is then dried to form a solid having a water content of lessthan about 1% by weight. The solid may then be reduced at atmosphericpressure in a hydrogen stream at 300° C. (uncalcined) or 400° C.(calcined) in a rotary ball furnace for 4 hours. After cooling andrendering the catalyst inert with nitrogen, 5% by volume of oxygen innitrogen is passed over the catalyst for 2 hours.

In certain embodiments, the catalyst described includes a catalystsupport. The catalyst support stabilizes and supports the catalyst. Thetype of catalyst support used depends on the chosen catalyst and thereaction conditions. Suitable supports for the invention include, butare not limited to, carbon, silica, silica-alumina, zirconia, titania,ceria, vanadia, nitride, boron nitride, heteropolyacids, hydroxyapatite,zinc oxide, chromia, zeolites, carbon nanotubes, carbon fullerene andany combination thereof.

The catalysts used in this invention can be prepared using conventionalmethods known to those in the art. Suitable methods may include, but arenot limited to, incipient wetting, evaporative impregnation, chemicalvapor deposition, wash-coating, magnetron sputtering techniques, and thelike.

The conditions for which to carry out the hydrogenation reaction willvary based on the type of starting material and the desired products.One of ordinary skill in the art, with the benefit of this disclosure,will recognize the appropriate reaction conditions. In general, thehydrogenation reaction is conducted at temperatures of 80° C. to 250°C., and preferably at 90° C. to 200° C., and most preferably at 100° C.to 150° C. In some embodiments, the hydrogenation reaction is conductedat pressures from 500 KPa to 14000 KPa.

The hydrogen used in the hydrogenolysis reaction of the currentinvention may include external hydrogen, recycled hydrogen, in situgenerated hydrogen, and any combination thereof. As used herein, theterm “external hydrogen” refers to hydrogen that does not originate fromthe biomass reaction itself, but rather is added to the system fromanother source.

In some embodiments of the invention, it is desirable to convert thestarting carbohydrate to a smaller molecule that will be more readilyconverted to desired higher hydrocarbons. One suitable method for thisconversion is through a hydrogenolysis reaction. Various processes areknown for performing hydrogenolysis of carbohydrates. One suitablemethod includes contacting a carbohydrate with hydrogen or hydrogenmixed with a suitable gas and a hydrogenolysis catalyst in ahydrogenolysis reactor under conditions sufficient to form a reactionproduct comprising smaller molecules or polyols. Here, the term “smallermolecules or polyols” includes any molecule that has a smaller molecularweight, which can include a lesser number of carbon atoms or oxygenatoms than the starting carbohydrate. In an embodiment, the reactionproducts include smaller molecules that include polyols and alcohols.Someone of ordinary skill in the art would be able to choose theappropriate method by which to carry out the hydrogenolysis reaction.

In some embodiments, a 5 and/or 6 carbon sugar or sugar alcohol may beconverted to propylene glycol, ethylene glycol, and glycerol using ahydrogenolysis catalyst. The hydrogenolysis catalyst may include Cr, Mo,W, Re, Mn, Cu, Cd, Fe, Co, Ni, Pt, Pd, Rh, Ru, Ir, Os, and alloys or anycombination thereof, either alone or with promoters such as Au, Ag, Cr,Zn, Mn, Sn, Bi, B, O, and alloys or any combination thereof. Thehydrogenolysis catalyst may also include a carbonaceous pyropolymercatalyst containing transition metals (e.g., chromium, molybdemum,tungsten, rhenium, manganese, copper, cadmium) or Group VIII metals(e.g., iron, cobalt, nickel, platinum, palladium, rhodium, ruthenium,iridium, and osmium). In certain embodiments, the hydrogenolysiscatalyst may include any of the above metals combined with an alkalineearth metal oxide or adhered to a catalytically active support. Incertain embodiments, the catalyst described in the hydrogenolysisreaction may include a catalyst support as described above for thehydrogenation reaction.

The conditions for which to carry out the hydrogenolysis reaction willvary based on the type of starting material and the desired products.One of ordinary skill in the art, with the benefit of this disclosure,will recognize the appropriate conditions to use to carry out thereaction. In general, they hydrogenolysis reaction is conducted attemperatures of 110° C. to 300° C., and preferably at 170° C. to 220°C., and most preferably at 200° C. to 225° C. In some embodiments, thehydrogenolysis reaction is conducted under basic conditions, preferablyat a pH of 8 to 13, and even more preferably at a pH of 10 to 12. Insome embodiments, the hydrogenolysis reaction is conducted at pressuresin a range between 60 KPa and 16500 KPa, and preferably in a rangebetween 1700 KPa and 14000 KPa, and even more preferably between 4800KPa and 11000 KPa.

The hydrogen used in the hydrogenolysis reaction of the currentinvention can include external hydrogen, recycled hydrogen, in situgenerated hydrogen, and any combination thereof.

In some embodiments, the reaction products discussed above may beconverted into higher hydrocarbons through a condensation reaction in acondensation reactor. In such embodiments, condensation of the reactionproducts occurs in the presence of a catalyst capable of forming higherhydrocarbons. While not intending to be limited by theory, it isbelieved that the production of higher hydrocarbons proceeds through astepwise addition reaction including the formation of carbon-carbon, orcarbon-oxygen bond. The resulting reaction products include any numberof compounds containing these moieties, as described in more detailbelow.

In certain embodiments, suitable condensation catalysts include an acidcatalyst, a base catalyst, or an acid/base catalyst. As used herein, theterm “acid/base catalyst” refers to a catalyst that has both an acid anda base functionality. In some embodiments the condensation catalyst caninclude, without limitation, zeolites, carbides, nitrides, zirconia,alumina, silica, aluminosilicates, phosphates, titanium oxides, zincoxides, vanadium oxides, lanthanum oxides, yttrium oxides, scandiumoxides, magnesium oxides, cerium oxides, barium oxides, calcium oxides,hydroxides, heteropolyacids, inorganic acids, acid modified resins, basemodified resins, and any combination thereof. In some embodiments, thecondensation catalyst can also include a modifier. Suitable modifiersinclude La, Y, Sc, P, B, Bi, Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, and anycombination thereof. In some embodiments, the condensation catalyst canalso include a metal. Suitable metals include Cu, Ag, Au, Pt, Ni, Fe,Co, Ru, Zn, Cd, Ga, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys,and any combination thereof.

In certain embodiments, the catalyst described in the condensationreaction may include a catalyst support as described above for thehydrogenation reaction. In certain embodiments, the condensationcatalyst is self-supporting. As used herein, the term “self-supporting”means that the catalyst does not need another material to serve assupport. In other embodiments, the condensation catalyst in used inconjunction with a separate support suitable for suspending thecatalyst. In an embodiment, the condensation catalyst support is silica.

The conditions under which the condensation reaction occurs will varybased on the type of starting material and the desired products. One ofordinary skill in the art, with the benefit of this disclosure, willrecognize the appropriate conditions to use to carry out the reaction.In some embodiments, the condensation reaction is carried out at atemperature at which the thermodynamics for the proposed reaction arefavorable. The temperature for the condensation reaction will varydepending on the specific starting polyol or alcohol. In someembodiments, the temperature for the condensation reaction is in a rangefrom 80° C. to 500° C., and preferably from 125° C. to 450° C., and mostpreferably from 125° C. to 250° C. In some embodiments, the condensationreaction is conducted at pressures in a range between 0 Kpa to 9000 KPa,and preferably in a range between 0 KPa and 7000 KPa, and even morepreferably between 0 KPa and 5000 KPa.

The higher alkanes formed by the invention include, but are not limitedto, branched or straight chain alkanes that have from 4 to 30 carbonatoms, branched or straight chain alkenes that have from 4 to 30 carbonatoms, cycloalkanes that have from 5 to 30 carbon atoms, cycloalkenesthat have from 5 to 30 carbon atoms, aryls, fused aryls, alcohols, andketones. Suitable alkanes include, but are not limited to, butane,pentane, pentene, 2-methylbutane, hexane, hexene, 2-methylpentane,3-methylpentane, 2,2,-dimethylbutane, 2,3-dimethylbutane, heptane,heptene, octane, octene, 2,2,4-trimethylpentane, 2,3-dimethyl hexane,2,3,4-trimethylpentane, 2,3-dimethylpentane, nonane, nonene, decane,decene, undecane, undecene, dodecane, dodecene, tridecane, tridecene,tetradecane, tetradecene, pentadecane, pentadecene, nonyldecane,nonyldecene, eicosane, eicosene, uneicosane, uneicosene, doeicosane,doeicosene, trieicosane, trieicosene, tetraeicosane, tetraeicosene, andisomers thereof. Some of these products may be suitable for use asfuels.

In some embodiments, the cycloalkanes and the cycloalkenes areunsubstituted. In other embodiments, the cycloalkanes and cycloalkenesare mono-substituted. In still other embodiments, the cycloalkanes andcycloalkenes are multi-substituted. In the embodiments comprising thesubstituted cycloalkanes and cycloalkenes, the substituted groupincludes, without limitation, a branched or straight chain alkyl having1 to 12 carbon atoms, a branched or straight chain alkylene having 1 to12 carbon atoms, a phenyl, and any combination thereof. Suitablecycloalkanes and cycloalkenes include, but are not limited to,cyclopentane, cyclopentene, cyclohexane, cyclohexene,methyl-cyclopentane, methyl-cyclopentene, ethyl-cyclopentane,ethyl-cyclopentene, ethyl-cyclohexane, ethyl-cyclohexene, isomers andany combination thereof.

In some embodiments, the aryls formed are unsubstituted. In anotherembodiment, the aryls formed are mono-substituted. In the embodimentscomprising the substituted aryls, the substituted group includes,without limitation, a branched or straight chain alkyl having 1 to 12carbon atoms, a branched or straight chain alkylene having 1 to 12carbon atoms, a phenyl, and any combination thereof. Suitable aryls forthe invention include, but are not limited to, benzene, toluene, xylene,ethyl benzene, para xylene, meta xylene, and any combination thereof.

The alcohols produced in the invention have from 4 to 30 carbon atoms.In some embodiments, the alcohols are cyclic. In other embodiments, thealcohols are branched. In another embodiment, the alcohols are straightchained. Suitable alcohols for the invention include, but are notlimited to, butanol, pentanol, hexanol, heptanol, octanol, nonanol,decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol,hexadecanol, heptyldecanol, octyldecanol, nonyldecanol, eicosanol,uneicosanol, doeicosanol, trieicosanol, tetraeicosanol, and isomersthereof.

The ketones produced in the invention have from 4 to 30 carbon atoms. Inan embodiment, the ketones are cyclic. In another embodiment, theketones are branched. In another embodiment, the ketones are straightchained. Suitable ketones for the invention include, but are not limitedto, butanone, pentanone, hexanone, heptanone, octanone, nonanone,decanone, undecanone, dodecanone, tridecanone, tetradecanone,pentadecanone, hexadecanone, heptyldecanone, octyldecanone,nonyldecanone, eicosanone, uneicosanone, doeicosanone, trieicosanone,tetraeicosanone, and isomers thereof.

Another such chemical modification is interesterification. Naturallyproduced glycerolipids do not have a uniform distribution of fatty acidconstituents. In the context of oils, interesterification refers to theexchange of acyl radicals between two esters of different glycerolipids.The interesterification process provides a mechanism by which the fattyacid constituents of a mixture of glycerolipids can be rearranged tomodify the distribution pattern. Interesterification is a well-knownchemical process, and generally comprises heating (to about 200° C.) amixture of oils for a period (e.g, 30 minutes) in the presence of acatalyst, such as an alkali metal or alkali metal alkylate (e.g., sodiummethoxide). This process can be used to randomize the distributionpattern of the fatty acid constituents of an oil mixture, or can bedirected to produce a desired distribution pattern. This method ofchemical modification of lipids can be performed on materials providedherein, such as microbial biomass with a percentage of dry cell weightas lipid at least 20%.

Directed interesterification, in which a specific distribution patternof fatty acids is sought, can be performed by maintaining the oilmixture at a temperature below the melting point of some TAGs whichmight occur. This results in selective crystallization of these TAGs,which effectively removes them from the reaction mixture as theycrystallize. The process can be continued until most of the fatty acidsin the oil have precipitated, for example. A directedinteresterification process can be used, for example, to produce aproduct with a lower calorie content via the substitution oflonger-chain fatty acids with shorter-chain counterparts. Directedinteresterification can also be used to produce a product with a mixtureof fats that can provide desired melting characteristics and structuralfeatures sought in food additives or products (e.g., margarine) withoutresorting to hydrogenation, which can produce unwanted trans isomers.

Interesterification of oils produced by the methods described herein canbe performed in conjunction with one or more of the methods and/ormaterials, or to produce products, as reported in the following: U.S.Pat. No. 6,080,853 (Nondigestible fat substitutes); U.S. Pat. No.4,288,378 (Peanut butter stabilizer); U.S. Pat. No. 5,391,383 (Ediblespray oil); U.S. Pat. No. 6,022,577 (Edible fats for food products);U.S. Pat. No. 5,434,278 (Edible fats for food products); U.S. Pat. No.5,268,192 (Low calorie nut products); U.S. Pat. No. 5,258,197 (Reducecalorie edible compositions); U.S. Pat. No. 4,335,156 (Edible fatproduct); U.S. Pat. No. 7,288,278 (Food additives or medicaments); U.S.Pat. No. 7,115,760 (Fractionation process); U.S. Pat. No. 6,808,737(Structural fats); U.S. Pat. No. 5,888,947 (Engine lubricants); U.S.Pat. No. 5,686,131 (Edible oil mixtures); and U.S. Pat. No. 4,603,188(Curable urethane compositions).

In one embodiment in accordance with the invention, transesterificationof the oil, as described above, is followed by reaction of thetransesterified product with polyol, as reported in U.S. Pat. No.6,465,642, to produce polyol fatty acid polyesters. Such anesterification and separation process may comprise the steps as follows:reacting a lower alkyl ester with polyol in the presence of soap;removing residual soap from the product mixture; water-washing anddrying the product mixture to remove impurities; bleaching the productmixture for refinement; separating at least a portion of the unreactedlower alkyl ester from the polyol fatty acid polyester in the productmixture; and recycling the separated unreacted lower alkyl ester.

Transesterification can also be performed on microbial biomass withshort chain fatty acid esters, as reported in U.S. Pat. No. 6,278,006.In general, transesterification may be performed by adding a short chainfatty acid ester to an oil in the presence of a suitable catalyst andheating the mixture. In some embodiments, the oil comprises about 5% toabout 90% of the reaction mixture by weight. In some embodiments, theshort chain fatty acid esters can be about 10% to about 50% of thereaction mixture by weight. Non-limiting examples of catalysts includebase catalysts, sodium methoxide, acid catalysts including inorganicacids such as sulfuric acid and acidified clays, organic acids such asmethane sulfonic acid, benzenesulfonic acid, and toluenesulfonic acid,and acidic resins such as Amberlyst 15. Metals such as sodium andmagnesium, and metal hydrides also are useful catalysts.

Another such chemical modification is hydroxylation, which involves theaddition of water to a double bond resulting in saturation and theincorporation of a hydroxyl moiety. The hydroxylation process provides amechanism for converting one or more fatty acid constituents of aglycerolipid to a hydroxy fatty acid. Hydroxylation can be performed,for example, via the method reported in U.S. Pat. No. 5,576,027.Hydroxylated fatty acids, including castor oil and its derivatives, areuseful as components in several industrial applications, including foodadditives, surfactants, pigment wetting agents, defoaming agents, waterproofing additives, plasticizing agents, cosmetic emulsifying and/ordeodorant agents, as well as in electronics, pharmaceuticals, paints,inks, adhesives, and lubricants. One example of how the hydroxylation ofa glyceride may be performed is as follows: fat may be heated,preferably to about 30-50° C. combined with heptane and maintained attemperature for thirty minutes or more; acetic acid may then be added tothe mixture followed by an aqueous solution of sulfuric acid followed byan aqueous hydrogen peroxide solution which is added in small incrementsto the mixture over one hour; after the aqueous hydrogen peroxide, thetemperature may then be increased to at least about 60° C. and stirredfor at least six hours; after the stirring, the mixture is allowed tosettle and a lower aqueous layer formed by the reaction may be removedwhile the upper heptane layer formed by the reaction may be washed withhot water having a temperature of about 60° C.; the washed heptane layermay then be neutralized with an aqueous potassium hydroxide solution toa pH of about 5 to 7 and then removed by distillation under vacuum; thereaction product may then be dried under vacuum at 100° C. and the driedproduct steam-deodorized under vacuum conditions and filtered at about50° to 60° C. using diatomaceous earth.

Hydroxylation of microbial oils produced by the methods described hereincan be performed in conjunction with one or more of the methods and/ormaterials, or to produce products, as reported in the following: U.S.Pat. No. 6,590,113 (Oil-based coatings and ink); U.S. Pat. No. 4,049,724(Hydroxylation process); U.S. Pat. No. 6,113,971 (Olive oil butter);U.S. Pat. No. 4,992,189 (Lubricants and lube additives); U.S. Pat. No.5,576,027 (Hydroxylated milk); and U.S. Pat. No. 6,869,597 (Cosmetics).The hydroxylation of ricinoleic acid provides a polyol.

Hydroxylated glycerolipids can be converted to estolides. Estolidesconsist of a glycerolipid in which a hydroxylated fatty acid constituenthas been esterified to another fatty acid molecule. Conversion ofhydroxylated glycerolipids to estolides can be carried out by warming amixture of glycerolipids and fatty acids and contacting the mixture witha mineral acid, as described by Isbell et al., JAOCS 71(2): 169-174(1994). Estolides are useful in a variety of applications, includingwithout limitation those reported in the following: U.S. Pat. No.7,196,124 (Elastomeric materials and floor coverings); U.S. Pat. No.5,458,795 (Thickened oils for high-temperature applications); U.S. Pat.No. 5,451,332 (Fluids for industrial applications); U.S. Pat. No.5,427,704 (Fuel additives); and U.S. Pat. No. 5,380,894 (Lubricants,greases, plasticizers, and printing inks).

Another such chemical modification is olefin metathesis. In olefinmetathesis, a catalyst severs the alkylidene carbons in an alkene(olefin) and forms new alkenes by pairing each of them with differentalkylidine carbons. The olefin metathesis reaction provides a mechanismfor processes such as truncating unsaturated fatty acid alkyl chains atalkenes by ethenolysis, cross-linking fatty acids through alkenelinkages by self-metathesis, and incorporating new functional groups onfatty acids by cross-metathesis with derivatized alkenes.

In conjunction with other reactions, such as transesterification andhydrogenation, olefin metathesis can transform unsaturated glycerolipidsinto diverse end products. These products include glycerolipid oligomersfor waxes; short-chain glycerolipids for lubricants; homo- andhetero-bifunctional alkyl chains for chemicals and polymers; short-chainesters for biofuel; and short-chain hydrocarbons for jet fuel. Olefinmetathesis can be performed on triacylglycerols and fatty acidderivatives, for example, using the catalysts and methods reported inU.S. Pat. No. 7,119,216, US Patent Pub. No. 2010/0160506, and U.S.Patent Pub. No. 2010/0145086.

Olefin metathesis of bio-oils generally comprises adding a solution ofRu catalyst at a loading of about 10 to 250 ppm under inert conditionsto unsaturated fatty acid esters in the presence (cross-metathesis) orabsence (self-metathesis) of other alkenes. The reactions are typicallyallowed to proceed from hours to days and ultimately yield adistribution of alkene products. One example of how olefin metathesismay be performed on a fatty acid derivative is as follows: A solution ofthe first generation Grubbs Catalyst(dichloro[2(1-methylethoxy-α-O)phenyl]methylene-α-C](tricyclohexyl-phosphine) in toluene at a catalyst loading of 222 ppmmay be added to a vessel containing degassed and dried methyl oleate.Then the vessel may be pressurized with about 60 psig of ethylene gasand maintained at or below about 30° C. for 3 hours, wherebyapproximately a 50% yield of methyl 9-decenoate may be produced.

Olefin metathesis of oils produced by the methods described herein canbe performed in conjunction with one or more of the methods and/ormaterials, or to produce products, as reported in the following: PatentApp. PCT/US07/081427 (α-olefin fatty acids) and U.S. patent applicationSer. No. 12/281,938 (petroleum creams), Ser. No. 12/281,931 (paintballgun capsules), Ser. No. 12/653,742 (plasticizers and lubricants), Ser.No. 12/422,096 (bifunctional organic compounds), and Ser. No. 11/795,052(candle wax).

Other chemical reactions that can be performed on microbial oils includereacting triacylglycerols with a cyclopropanating agent to enhancefluidity and/or oxidative stability, as reported in U.S. Pat. No.6,051,539; manufacturing of waxes from triacylglycerols, as reported inU.S. Pat. No. 6,770,104; and epoxidation of triacylglycerols, asreported in “The effect of fatty acid composition on the acrylationkinetics of epoxidized triacylglycerols”, Journal of the American OilChemists' Society, 79:1, 59-63, (2001) and Free Radical Biology andMedicine, 37:1, 104-114 (2004).

The generation of oil-bearing microbial biomass for fuel and chemicalproducts as described above results in the production of delipidatedbiomass meal. Delipidated meal is a byproduct of preparing algal oil andis useful as animal feed for farm animals, e.g., ruminants, poultry,swine and aquaculture. The resulting meal, although of reduced oilcontent, still contains high quality proteins, carbohydrates, fiber,ash, residual oil and other nutrients appropriate for an animal feed.Because the cells are predominantly lysed by the oil separation process,the delipidated meal is easily digestible by such animals. Delipidatedmeal can optionally be combined with other ingredients, such as grain,in an animal feed. Because delipidated meal has a powdery consistency,it can be pressed into pellets using an extruder or expander or anothertype of machine, which are commercially available.

Castor oil is a naturally occurring oil isolated from castor beans.Hydrolysis of castor oil yields ricinoleic acid. The production ofcastor oil from castor beans is difficult because castor beans containhigh amounts of ricin. Ricin is an extremely dangerous toxin listed as aschedule 1 compound in the Chemical Weapons Convention. Great care musttherefore be taken in the production of castor oil from castor beans. Ahydroxylated oil isolated from a microalgal cell is provided by anembodiment of the invention. In this way, ricinoleic acid can beproduced. In one embodiment, the hydroxylated oil is a hydroxylatedtriglyceride. The hydroxylated triglyceride of the present invention maybe chemically similar to castor oil. As shown in Example 7, theinvention provides a hydroxylated microbial oil. The oil of Example 7,when analyzed by GC/MS, showed that the inventors have producedricinoleic acid (12-hydroxy-9-cis-octadecenoic acid).

A fatty acid in accordance with an embodiment of the invention is ahydroxylated fatty acid. One embodiment of the hydroxylated fatty acidis ricinoleic acid.

The microbial hydroxylated oil or hydroxylated fatty acid can be furtherhydroxylated. When ricinoleic acid is further hydroxylated, a fatty acidcontaining two hydroxyl groups, a polyol, is provided.

The invention provides a composition prepared by reacting a polyol(e.g., hydroxylated oil and/or a hydroxylated fatty acid) with acompound that contains an isocyanate moiety. Polyurethanes using castoroil and an isocyanate have been produced. Polyurethanes are ubiquitousin the products we use today. Polyurethanes are found in automobiles,toys, athletic equipment, consumer electronics, shoes, mattresses,cushions, adhesives, construction materials, and the like. Currently,polyurethanes made with castor oil are commercially available from BASF,Itoh Oil and others. Polyurethanes made with hydroxylated soybean oilare commercially available from Cargill, Dow, Bayer and others.

In an embodiment, ricinoleic acid produced by the microbial cells may befurther processed into an oleochemical product, including a ricinoleicester, ricinoleic amide, polyurethane, polyurethane foam, orpolyurethane part according to methods known in the art. See, forexample, U.S. Pat. Nos. 6,194,475, 4,266,617, 6,403,664, and 4,058,492,and US Patent Application No. 20100227151.

The invention, having been described in detail above, is exemplified inthe following examples, which are offered to illustrate, but not tolimit, the claimed invention.

VII. EXAMPLES Example 1: Methods for Culturing Prototheca

Prototheca strains were cultivated to achieve a high percentage of oilby dry cell weight. Cryopreserved cells were thawed at room temperatureand 500 ul of cells were added to 4.5 ml of medium (4.2 g/L K₂HPO₄, 3.1g/L NaH₂PO₄, 0.24 g/L MgSO₄.7H₂O, 0.25 g/L Citric Acid monohydrate,0.025 g/L CaCl₂ 2H₂O, 2 g/L yeast extract) plus 2% glucose and grown for7 days at 28° C. with agitation (200 rpm) in a 6-well plate. Dry cellweights were determined by centrifuging 1 ml of culture at 14,000 rpmfor 5 min in a pre-weighed Eppendorf tube. The culture supernatant wasdiscarded and the resulting cell pellet washed with 1 ml of deionizedwater. The culture was again centrifuged, the supernatant discarded, andthe cell pellets placed at −80° C. until frozen. Samples were thenlyophilized for 24 hrs and dry cell weights calculated. Fordetermination of total lipid in cultures, 3 ml of culture was removedand subjected to analysis using an Ankom system (Ankom Inc., Macedon,N.Y.) according to the manufacturer's protocol. Samples were subjectedto solvent extraction with an Amkom XT10 extractor according to themanufacturer's protocol. Total lipid was determined as the difference inmass between acid hydrolyzed dried samples and solvent extracted, driedsamples. Percent oil dry cell weight measurements are shown in Table 10.

TABLE 10 Percent oil by dry cell weight Species Strain % Oil Protothecastagnora UTEX 327 13.14 Prototheca moriformis UTEX 1441 18.02 Protothecamoriformis UTEX 1435 27.17

Microalgae samples from multiple strains from the genus Prototheca weregenotyped. Genomic DNA was isolated from algal biomass as follows. Cells(approximately 200 mg) were centrifuged from liquid cultures 5 minutesat 14,000×g. Cells were then resuspended in sterile distilled water,centrifuged 5 minutes at 14,000×g and the supernatant discarded. Asingle glass bead ˜2 mm in diameter was added to the biomass and tubeswere placed at −80° C. for at least 15 minutes. Samples were removed and150 μl of grinding buffer (1% Sarkosyl, 0.25 M Sucrose, 50 mM NaCl, 20mM EDTA, 100 mM Tris-HCl, pH 8.0, RNase A 0.5 ug/ul) was added. Pelletswere resuspended by vortexing briefly, followed by the addition of 40 ulof 5M NaCl. Samples were vortexed briefly, followed by the addition of66 μl of 5% CTAB (Cetyl trimethylammonium bromide) and a final briefvortex. Samples were next incubated at 65° C. for 10 minutes after whichthey were centrifuged at 14,000×g for 10 minutes. The supernatant wastransferred to a fresh tube and extracted once with 300 μl ofPhenol:Chloroform:Isoamyl alcohol 12:12:1, followed by centrifugationfor 5 minutes at 14,000×g. The resulting aqueous phase was transferredto a fresh tube containing 0.7 vol of isopropanol (˜190 μl), mixed byinversion and incubated at room temperature for 30 minutes or overnightat 4° C. DNA was recovered via centrifugation at 14,000×g for 10minutes. The resulting pellet was then washed twice with 70% ethanol,followed by a final wash with 100% ethanol. Pellets were air dried for20-30 minutes at room temperature followed by resuspension in 50 μl of10 mM TrisCl, 1 mM EDTA (pH 8.0).

Five μl of total algal DNA, prepared as described above, was diluted1:50 in 10 mM Tris, pH 8.0. PCR reactions, final volume 20 μl, were setup as follows. Ten μl of 2× iProof HF master mix (BIO-RAD) was added to0.4 μl primer SZ02613 (5′-TGTTGAAGAATGAGCCGGCGAC-3′ (SEQ ID NO:9) at 10mM stock concentration). This primer sequence runs from position 567-588in Gen Bank accession no. L43357 and is highly conserved in higherplants and algal plastid genomes. This was followed by the addition of0.4 μl primer SZ02615 (5′-CAGTGAGCTATTACGCACTC-3′ (SEQ ID NO:10) at 10mM stock concentration). This primer sequence is complementary toposition 1112-1093 in Gen Bank accession no. L43357 and is highlyconserved in higher plants and algal plastid genomes. Next, 5 μl ofdiluted total DNA and 3.2 μl dH₂O were added. PCR reactions were run asfollows: 98° C., 45″; 98° C., 8″; 53° C., 12″; 72° C., 20″ for 35 cyclesfollowed by 72° C. for 1 min and holding at 25° C. For purification ofPCR products, 20 μl of 10 mM Tris, pH 8.0, was added to each reaction,followed by extraction with 40 μl of Phenol:Chloroform:isoamyl alcohol12:12:1, vortexing and centrifuging at 14,000×g for 5 minutes. PCRreactions were applied to S-400 columns (GE Healthcare) and centrifugedfor 2 minutes at 3,000×g. Purified PCR products were subsequently TOPOcloned into PCR8/GW/TOPO and positive clones selected for on LB/Specplates. Purified plasmid DNA was sequenced in both directions using M13forward and reverse primers. In total, twelve Prototheca strains wereselected to have their 23 S rRNA DNA sequenced and the sequences arelisted in the Sequence Listing. A summary of the strains and SequenceListing Numbers is included below. The sequences were analyzed foroverall divergence from the UTEX 1435 (SEQ ID NO: 15) sequence. Twopairs emerged (UTEX 329/UTEX 1533 and UTEX 329/UTEX 1440) as the mostdivergent. In both cases, pairwise alignment resulted in 75.0% pairwisesequence identity. The percent sequence identity to UTEX 1435 is alsoincluded below:

Species Strain % nt identity SEQ ID NO. Prototheca kruegani UTEX 32975.2 SEQ ID NO: 11 Prototheca wickerhamii UTEX 1440 99 SEQ ID NO: 12Prototheca stagnora UTEX 1442 75.7 SEQ ID NO: 13 Prototheca moriformisUTEX 288 75.4 SEQ ID NO: 14 Prototheca moriformis UTEX 1439; 100 SEQ IDNO: 15 1441; 1435; 1437 Prototheca wikerhamii UTEX 1533 99.8 SEQ ID NO:16 Prototheca moriformis UTEX 1434 75.9 SEQ ID NO: 17 Prototheca zopfiiUTEX 1438 75.7 SEQ ID NO: 18 Prototheca moriformis UTEX 1436 88.9 SEQ IDNO: 19

Lipid samples from a subset of the above-listed strains were analyzedfor lipid profile using HPLC. Results are shown below in Table 11.Alternatively, lipid profiles can be determined using the procedureoutlines in Example 11.

TABLE 11 Diversity of lipid chains in Prototheca species Strain C14:0C16:0 C16:1 C18:0 C18:1 C18:2 C18:3 C20:0 C20:1 UTEX 0 12.01 0 0 50.3317.14 0 0 0 327 UTEX 1.41 29.44 0.70 3.05 57.72 12.37 0.97 0.33 0 1441UTEX 1.09 25.77 0 2.75 54.01 11.90 2.44 0 0 1435

Oil extracted from Prototheca moriformis UTEX 1435 (via solventextraction or using an expeller press was analyzed for carotenoids,chlorophyll, tocopherols, other sterols and tocotrienols. The resultsare summarized below in Table 12.

TABLE 12 Carotenoid, chlorophyll, tocopherol/sterols and tocotrienolanalysis in oil extracted from Prototheca moriformis (UTEX 1435).Pressed oil Solvent extracted (mcg/ml) oil (mcg/ml) cis-Lutein 0.0410.042 trans-Lutein 0.140 0.112 trans-Zeaxanthin 0.045 0.039cis-Zeaxanthin 0.007 0.013 t-alpha-Crytoxanthin 0.007 0.010t-beta-Crytoxanthin 0.009 0.010 t-alpha-Carotene 0.003 0.001c-alpha-Carotene none detected none detected t-beta-Carotene 0.010 0.0099-cis-beta-Carotene 0.004 0.002 Lycopene none detected none detectedTotal Carotenoids 0.267 0.238 Chlorophyll <0.01 mg/kg <0.01 mg/kgTocopherols and Sterols gamma Tocopherol 0.49 0.49 Campesterol 6.09 6.05Stigmasterol 47.6 47.8 Beta-sitosterol 11.6 11.5 Other sterols 445 446Tocotrienols alpha Tocotrienol 0.26 0.26 beta Tocotrienol <0.01 <0.01gamma Tocotrienol 0.10 0.10 detal Tocotrienol <0.01 <0.01 TotalTocotrienols 0.36 0.36

Oil extracted from Prototheca moriformis, from four separate lots, wererefined and bleached using standard vegetable oil processing methods.Briefly, crude oil extracted from Prototheca moriformis was clarified ina horizontal decanter, where the solids were separated from the oil. Theclarified oil was then transferred to a tank with citric acid and waterand left to settle for approximately 24 hours. After 24 hours, themixture in the tank formed 2 separate layers. The bottom layer wascomposed of water and gums that were then removed by decantation priorto transferring the degummed oil into a bleaching tank. The oil was thenheated along with another dose of citric acid. Bleaching clay was thenadded to the bleaching tank and the mixture was further heated undervacuum in order to evaporate off any water that was present. The mixturewas then pumped through a leaf filter in order to remove the bleachingclay. The filtered oil was then passed through a final 5 μm polishingfilter and then collected for storage until use. The refined andbleached (RB) oil was then analyzed for carotenoids, chlorophyll,sterols, tocotrienols and tocopherols. The results of these analyses aresummarized in Table 13 below. “Nd” denotes none detected and thesensitivity of detection is listed below:

Sensitivity of Detection

-   -   Carotenoids (mcg/g) nd=<0.003 mcg/g    -   Chlorophyll (mcg/g) nd=<0.03 mcg/g    -   Sterols (%) nd=0.25%    -   Tocopherols (mcg/g); nd=3 mcg/g

TABLE 13 Carotenoid, chlorophyll, sterols, tocotrienols and tocopherolanalysis from refined and bleached Prototheca moriformis oil. Lot A LotB Lot C Lot D Carotenoids (mcg/g) Lutein 0.025 0.003 nd 0.039 Zeaxanthinnd nd nd nd cis-Lutein/Zeaxanthin nd nd nd nd trans-alpha-Cryptoxanthinnd nd nd nd trans-beta-Cryptoxanthin nd nd nd nd trans-alpha-Carotene ndnd nd nd cis-alpha-Carotene nd nd nd nd trans-beta-Carotene nd nd nd ndcis-beta-Carotene nd nd nd nd Lycopene nd nd nd nd Unidentified 0.2190.066 0.050 0.026 Total Carotenoids 0.244 0.069 0.050 0.065 Chlorophyll(mcg/g) Chlorophyll A 0.268 0.136 0.045 0.166 Chlorophyll B nd nd nd ndTotal Chlorophyll 0.268 0.136 0.045 0.166 Sterols (%) Brassicasterol ndnd nd nd Campesterol nd nd nd nd Stigmasterol nd nd nd ndbeta-Sitosterol nd nd nd nd Total Sterols nd nd nd nd Tocopherols(mcg/g) alpha-Tocopherol 23.9 22.8 12.5 8.2 beta-Tocopherol 3.72 nd ndnd gamma-Tocopherol 164 85.3 43.1 38.3 delta-Tocopherol 70.1 31.1 18.114.3 Total Tocopherols 262 139.2 73.7 60.8 Tocotrienols (mcg/g)alpha-Tocotrienol 190 225 253 239 beta-Tocotrienol nd nd nd ndgamma-Tocotrienol 47.3 60.4 54.8 60.9 delta-Tocotrienol 12.3 16.1 17.515.2 Total Tocotrienols 250 302 325 315

The same four lots of Prototheca moriformis oil was also analyzed fortrace elements and the results are summarized below in Table 14.

TABLE 14 Elemental analysis of refined and bleached Protothecamoriformis oil. Lot A Lot B Lot C Lot D Elemental Analysis (ppm) Calcium0.08 0.07 <0.04 0.07 Phosphorous <0.2 0.38 <0.2 0.33 Sodium <0.5 0.55<0.5 <0.5 Potassium 1.02 1.68 <0.5 0.94 Magnesium <0.04 <0.04 <0.04 0.07Manganese <0.05 <0.05 <0.05 <0.05 Iron <0.02 <0.02 <0.02 <0.02 Zinc<0.02 <0.02 <0.02 <0.02 Copper <0.05 <0.05 <0.05 <0.05 Sulfur 2.55 4.452.36 4.55 Lead <0.2 <0.2 <0.2 <0.2 Silicon 0.37 0.41 0.26 0.26 Nickel<0.2 <0.2 <0.2 <0.2 Organic chloride <1.0 <1.0 <1.0 2.2 Inorganicchloride <1.0 <1.0 <1.0 <1.0 Nitrogen 4.4 7.8 4.2 6.9 Lithium <0.02<0.02 <0.02 <0.02 Boron 0.07 0.36 0.09 0.38 Aluminum — <0.2 <0.2 <0.2Vanadium <0.05 <0.05 <0.05 <0.05 Lovibond Color (°L) Red 5.0 4.3 3.2 5.0Yellow 70.0 70.0 50.0 70.0 Mono & Diglycerides by HPLC (%) Diglycerides1.68 2.23 1.25 1.61 Monoglycerides 0.03 0.04 0.02 0.03 Free fatty acids(FFA) 1.02 1.72 0.86 0.83 Soaps 0 0 0 Oxidized and PolymerizedTriglycerides Oxidized Triglycerides (%) 3.41 2.41 4.11 1.00 PolymerizedTriglycerides 1.19 0.45 0.66 0.31 (%) Peroxide Value (meg/kg) 0.75 0.800.60 1.20 p-Anisidine value 5.03 9.03 5.44 20.1 (dimensionless) Waterand Other Impurities (%) Karl Fisher Moisture 0.8 0.12 0.07 0.18 Totalpolar compounds 5.02 6.28 4.54 5.23 Unsaponificable matter 0.92 1.070.72 1.04 Insoluble impurities <0.01 <0.01 0.01 <0.01 Total oil (%)Neutral oil 98.8 98.2 99.0 98.9

Example 2: General Methods for Biolistic Transforming Prototheca

Seashell Gold Microcarriers 550 nanometers were prepared according tothe protocol from manufacturer. Plasmid (20 μg) was mixed with 50 μl ofbinding buffer and 60 μl (30 mg) of S550d gold carriers and incubated inice for 1 min. Precipitation buffer (100 μl) was added, and the mixturewas incubated in ice for another 1 min. After vortexing, DNA-coatedparticles were pelleted by spinning at 10,000 rpm in an Eppendorf 5415Cmicrofuge for 10 seconds. The gold pellet was washed once with 500 μl ofcold 100% ethanol, pelleted by brief spinning in the microfuge, andresuspended with 50 μl of ice-cold ethanol. After a brief (1-2 sec)sonication, 10 μl of DNA-coated particles were immediately transferredto the carrier membrane.

Prototheca strains were grown in proteose medium (2 g/L yeast extract,2.94 mM NaNO3, 0.17 mM CaCl2*2H2O, 0.3 mM MgSO4.7H2O, 0.4 mM K2HPO4,1.28 mM KH2PO4, 0.43 mM NaCl) with 2% glucose on a gyratory shaker untilit reaches a cell density of 2×10⁶ cells/ml. The cells were harvested,washed once with sterile distilled water, and resuspended in 50 μl ofmedium. 1×10⁷ cells were spread in the center third of a non-selectiveproteose media plate. The cells were bombarded with the PDS-1000/HeBiolistic Particle Delivery system (Bio-Rad). Rupture disks (1350 psi)were used, and the plates are placed 6 cm below the screen/macrocarrierassembly. The cells were allowed to recover at 25° C. for 12-24 h. Uponrecovery, the cells were scraped from the plates with a rubber spatula,mixed with 100 μl of medium and spread on plates containing theappropriate antibiotic selection. After 7-10 days of incubation at 25°C., colonies representing transformed cells were visible on the plates.Colonies were picked and spotted on selective (either antibiotic orcarbon source) agar plates for a second round of selection.

Example 3: Expression of Various Thioesterases in Prototheca

Methods and effects of expressing a heterologous thioesterase gene inPrototheca species have been previously described in PCT Application No.PCT/US2009/066142, hereby incorporated by reference. The effect of otherthioesterase genes/gene products from higher plants species was furtherinvestigated. These thioesterases include thioesterases from thefollowing higher plants:

GenBank Species Accession No. Specificity SEQ ID NO: Cinnamomum Q39473C14 SEQ ID NOs: 30-31 camphora Umbellularia Q41635 C10-C12 SEQ ID NOs:34-35 californica Cuphea hookeriana AAC49269 C8-C10 SEQ ID NOs: 32-33Cuphea palustris AAC49179 C8 SEQ ID NOs: 36-37 Cuphea lanceolataCAB60830 C10 SEQ ID NOs: 38-39 Iris germanica AAG43858.1 C14 SEQ ID NOs:40-41 Myristica fragrans AAB717291.1 C14 SEQ ID NOs: 42-43 Cupheapalustris AAC49180 C14 SEQ ID NOs: 44-45 Ulmus americana AAB71731 broadSEQ ID NOs: 46-47 Myristica fragrans AAB71729 broad SEQ ID NOs: 145-146Garcinia AAB51525.1 C16 SEQ ID NOs: 147-148 mangostana Cuphea hookerianaQ39513.1 C16 SEQ ID NOs: 149-150 Elaeis guiniensis AAD42220.2 C16 SEQ IDNO: 151-152 Brassica napus CAA52070.1 C18 SEQ ID NO: 153-154 Ricinuscommunis AB530422.1 C18:1 SEQ ID NO: 155-156

In all cases, each of the above thioesterase constructs was transformedin to Prototheca moriformis (UTEX 1435) using biolistic particlebombardment. Other transformation methods including homologousrecombination as disclosed in PCT Application No. PCT/US2009/066142,would also be suitable for heterologous expression of genes of interest.Transformation of Prototheca moriformis (UTEX 1435) with each of theabove thioesterase constructs was performed using the methods describedin Example 2. Each of the constructs contained a NeoR gene and selectionfor positive clones was carried out using 100 μg/ml G418. All codingregions were codon optimized to reflect the codon bias inherent inPrototheca moriformis UTEX 1435 (see Table 2) nuclear genes. Both aminoacid sequences and the cDNA sequences for the construct used are listedin the sequence identity listing. Unless otherwise specified, thetransit peptide for each of the higher plant thioesterase was replacedwith an algal codon optimized transit peptide from Prototheca moriformisdelta 12 fatty acid desaturase (SEQ ID NO: 48)) or from Chlorellaprotothecoides stearoyl ACP desaturase (SEQ ID NO: 49). All thioesteraseconstructs were driven by the Chlamydomanas reinhardtii beta-tubulinpromoter/5′UTR. Growth and lipid production of selected positive cloneswere compared to wildtype (untransformed) Prototheca moriformis (UTEX1435). Wildtype and selected positive clones were grown on 2% glucoseG418 plates. Lipid profiles analysis on selected positive clones foreach construct is summarized below (expressed in Area %) in Table 15.

TABLE 15 Lipid profiles of Prototheca moriformis expressing variousheterologous thioesterases. UTEX Thioesterase Fatty 1435 U. C. palustrisC. palustris U. Acid wt californica C. camphora I. germanica M. fragransC8:0 C. hookeriana C. lanceolata C14:0 americana C8:0 0 0 0 0 3.1 1.8 00 .09 C10:0 0.02 .07 .02 .01 .09 .56 6.85 1.91 .01 2.85 C12:0 0.05 141.82 .09 .05 .25 .2 .29 .06 .74 C14:0 1.65 3 17.3 2.59 5.31 1.45 1.81.83 2.87 10.45 C16:0 28.0 21.4 24.3 26.52 31.08 22.84 23.9 25.55 27.2333.3 C18:0 2.9 2.9 2.7 3.11 2.71 3.24 2.8 3.26 3.62 3.47 C18:1 53.8 45.241.3 49.96 39.77 56.62 49.8 55.43 51.04 38.71 C18:2 10.95 10 9.7 11.8614.17 8.24 9.7 8.17 10.81 7.38 C18:3 α 0.8 .86 .8 .40 .64 .61 .9 .58 .97.52 Total 32.62 44.97 46.14 32.32 39.24 31.44 37.35 32.84 33.79 50.9saturates (area %)

The results show that all of the thioesterases expressed impacted fattyacid profiles to some level. Looking at the “Total saturates” row, thedegree of saturation was profoundly impacted by the expression ofseveral of the thioesterases, including those from U. californica, C.camphora, and most notably, U. americana. These changes in thepercentage of total saturates were unexpected in that the heterologousexpression of thioesterases from higher plants can apparently impactmore than just lipid chain lengths; it can also impact other attributesof lipid profiles produced by microalgae, namely the degree ofsaturation of the fatty acids.

Selected clones transformed with C. palustris C8 thioesterase, C.hookeriana thioesterase, U. californica and C. camphora thioesterasewere further grown in varying amounts of G418 (from 25 mg/L to 50 mg/L)and at varying temperatures (from 22° C. to 25° C.) and the lipidprofile was determined for these clones. Table 16 summarizes the lipidprofile (in Area %) of representative clones containing eachthioesterase. A second construct containing the U. americanathioesterase was constructed and transformed into Prototheca moriformis(UTEX 1435) using the biolistic methods described above. This secondconstruct was introduced into the cell via homologous recombination.Methods of homologous recombination in Prototheca species were describedpreviously in PCT Application No. PCT/US2009/66142. The homologous DNAthat was used was from the 6S genomic DNA sequence from Protothecamoriformis UTEX 1435 (donor sequences given in SEQ ID 92 and SEQ ID 84)The selection agent was the ability to grow on sucrose, using a codonoptimized suc2 gene from S. cereveisiae driven by the C. reinhardtiibeta tubulin promoter. The native U. americana transit peptide wasreplaced by the Chlorella protothecoides (UTEX 250) stearoyl ACPdesaturase transit peptide. The cDNA of this construct is listed in theSequence Listing as SEQ ID NO: 50. Selection of positive clones wasperformed on 2% sucrose plates and the resulting cultures for lipidprofile determination was also grown on 2% sucrose containing medium. Arepresentative lipid profile for this Prototheca moriformis straincontaining a homologously recombined heterologous U. americanathioesterase is summarized in Table 16.

TABLE 16 Lipid profiles of Prototheca moriformis strains containingheterologous thioesterase genes. C. palustris U. americana C8 C.hookeriana C. camphora 2 C8:0 12.28 2.37 0 0 C10:0 2.17 12.09 0.02 4.69C12:0 0.34 0.33 3.81 1.02 C14:0 1.59 2.08 32.73 16.21 C16:0 15.91 20.0724.03 38.39 C18:0 1.59 1.57 1.21 2.83 C18:1 50.64 41.80 18.64 27.22C18:2 13.02 16.37 16.57 7.65 C18:3 α 1.52 1.75 1.66 0.74 Total 33.8838.51 61.80 63.14 saturates

As with the clones described above, all transformants containing aheterologous thioesterase gene showed impacted fatty acid profiles tosome level, and the total percent of saturated fatty acids were alsochanged, as compared to wildtype (untransformed) Prototheca moriformis.The Prototheca moriformis containing the U. americana thioesteraseintroduced by homologous recombination had the greatest increase intotal saturates.

Additionally, transgenic clones containing the exogenous C. hookeriana,C. camphora, U. californica or U. americana thioesterase were assessedfor novel lipid profiles. The C. hookeriana thioesterase containingclone achieved the following lipid profile when grown in 2% glucose, 25mg/ml G418 at 22° C.: 5.10% C8:0; 18.28% C10:0; 0.41% C12:0; 1.76%C14:0; 16.31% C16:0; 1.40% C18:0; 40.49% C18:1; and 13.16% C18:2. The C.camphora thioesterase-containing clone (also containing an exogenoussucrose invertase) achieved the following lipid profile when grown in 2%sucrose at 25° C.: 0.04% C10:0; 6.01% C12:0; 35.98% C14:0; 19.42 C16:0;1.48% C18:0; 25.44% C18:1; and 9.34% C18:2. The U. calfornicathioesterase containing clone achieved the following lipid profile whengrown in 2% glucose, 25-100 mg/ml G418 at 22° C.: 0% C8:0; 0.11% C10:0;34.01% C12:0; 5.75% C14:0; 14.02% C16:0; 1.10% C18:0; 28.93% C18:1; and13.01% C18:2. The U. americana thioesterase containing clone achievedthe following lipid profile when grown in 2% glucose at 28° C.: 1.54%C10:0; 0.43% C12:0; 7.56% C14:0; 39.45% C16:0; 2.49% C18:0; 38.49%C18:1; and 7.88% C18:2.

Additional thioesterases from higher plants were also introduced into aPrototheca moriformis UTEX 1435 genetic background, and thecodon-optimized cDNA sequences and amino acid sequences are listed inthe Sequence Listing as specified above. These additional thioesterasesinclude a broad specificity thioesterase (C14:0-C18:0) from Myristicafragrans, a C16:0-preferring thioesterase from Garcinia mangostana, aC16:0-preferring thioesterase from Cuphea hookeriana, a C16:0-preferringthioesterase from Elaeis guiniensis, a C18:0-preferring thioesterasefrom Brassica napus, and a C18:1-preferring thioesterase from Ricinuscommunis. Details of the expression constructs and the resultingtransgenic clones from each of the above transgene/transformations aredescribed below.

A broad specificity thioesterase (C14:0-C18:0) thioesterase fromMyristica fragrans was introduced into a Prototheca moriformis UTEX 1435genetic background using methods described above. Two differentexpression constructs were tested, each containing a different plastidtargeting sequences. In both constructs, the S. cerevisiae sucroseinvertase gene suc2 was utilized as a selectable marker, conferring topositive transformants the ability to grow on plates with sucrose as thesole carbon source. Both expression constructs, pSZ1318 and pSZ1317contained a 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologousrecombination targeting sequences (flanking the construct) to the 6Sgenomic region for integration into the nuclear genome and a S.cerevisiae suc2 sucrose invertase coding region under the control of C.reinhardtii β-tubulin promoter/5′UTR and Chlorella vulgaris nitratereductase 3′ UTR. This S. cerevisiae suc2 expression cassette is listedas SEQ ID NO: 159. pSZ1318 contained the M. fragrans thioesterase codingregion with the native transit peptide replaced with the transit peptidefrom Prototheca moriformis delta 12 FAD (SEQ ID NO: 48) under thecontrol of the Prototheca moriformis Amt03 promoter (SEQ ID NO: 89) andthe C. vulgaris nitrate reductase 3′UTR. The codon-optimized M. fragransthioesterase with the transit peptide from Prototheca moriformis delta12 FAD is listed as SEQ ID NO: 145. pSZ1317 contained the M. fragranscoding region with the native transit peptide replaced with the transitpeptide from Chlorella protothecoides stearoyl ACP desaturase (SEQ IDNO: 49) under the control of the Prototheca moriformis Amt03 promoter(SEQ ID NO: 89) and the C. vulgaris nitrate reductase 3′ UTR. Thecodon-optimized M. fragrans thioesterase with the transit peptide fromC. protothecoides stearoyl ACP desaturase is listed as SEQ ID NO: 158.Both expression constructs, pSZ1318 and pSZ1317 were transformed intoPrototheca cells and selection was carried out on plates where sucrosewas the sole-carbon source. Positive clones were selected from eachtransformation and grown in medium with sucrose as the sole carbonsource under nitrogen-limited conditions for lipid production. Lipidprofiles of a subset of the positive clones selected were determinedusing direct transesterification methods described above and aresummarized in Table 17.

TABLE 17 Lipid profiles of Myristica fragrans broad specificitythioesterase transgenic Prototheca cells. Strain C10:0 C12:0 C14:0 C16:0C18:0 C18:1 C18:2 wildtype 0.01 0.03 1.17 25.86 2.84 58.33 9.16 pSZ13180.03 0.23 16.09 37.72 6.11 27.39 9.98 clone A pSZ1318 0.03 0.22 15.7437.17 6.23 28.16 9.94 clone B pSZ1318 0.03 0.22 14.97 36.05 5.87 30.489.86 clone C pSZ1317 0.02 0.21 15.23 36.62 5.11 31.83 8.76 clone ApSZ1317 0.03 0.27 18.06 38.88 5.64 26.11 8.90 clone B pSZ1317 0.02 0.2416.19 37.02 5.61 29.52 9.19 clone C

The positive clones containing a Myristica fragrans thioesterasetransgene displayed altered lipid profiles. However, the abovesummarized results showed an unexpected result; in higher plants, theMyristica fragrans thioesterase exhibits significant activity on C16:0fatty acyl-ACPs (Voelker et al., 1997), whereas, in Prototheca cells,the Myristica fragrans thioesterase seem to have a gradation of impacton C14:0>C18:0>C16:0 and is more broad based than just C16:0.

A C16:0-preferring thioesterase from Garcinia mangostana was introducedinto a Prototheca moriformis UTEX 1435 genetic background, and thecodon-optimized cDNA sequences and amino acid sequences are listed inthe Sequence Listing as specified above. The expression constructcontained a 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologousrecombination targeting sequences (flanking the construct) to the 6Sgenomic region for integration into the nuclear genome and a S.cerevisiae suc2 sucrose invertase coding region under the control of C.reinhardtii β-tubulin promoter/5′UTR and Chlorella vulgaris nitratereductase 3′ UTR. This S. cerevisiae suc2 expression cassette is listedas SEQ ID NO: 159 and served as a selection marker. The G. manogstanacoding region was under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR.The G. manogstana native transit peptide was also replaced with thetransit peptide from C. protothecoides stearoyl desaturase (SEQ ID NO:49) and the cDNA sequence of the thioesterase with the replaced transitpeptide is listed as SEQ ID NO: 147. The entire Garcinia mangostanaexpression cassette was termed pSZ1452 and transformed into a Protothecamoriformis genetic background. Positive clones were screened on plateswith sucrose as the sole carbon source. A subset of the positive cloneswere selected and grown under lipid production conditions and lipidprofiles were determined using direct transesterification methods asdescribed above. The lipid profiles of the selected clones aresummarized in Table 18 below.

TABLE 18 Lipid profiles of Garcinia mangostana C16:0-preferringthioesterase transgenic Prototheca cells. Strain C10:0 C12:0 C14:0 C16:0C18:0 C18:1 C18:2 wildtype 0.01 0.03 1.17 25.86 2.84 58.33 9.16 pSZ14520.02 0.07 5.52 62.77 4.36 18.99 6.29 clone A pSZ1452 0.02 0.08 5.6961.66 4.76 19.28 6.54 clone B pSZ1452 0.01 0.05 3.44 57.97 4.21 24.767.38 clone C

The results show that transformants with the G. mangostana thioesterasetransgene have significantly impacted C16:0 fatty acid levels and to alesser extent, impacted C14:0 and C18:0 fatty acid levels, along with asharp decrease in C18:1 fatty acid levels as compared to wildtype.

A C16:0-preferring thioesterase from Cuphea hookeriana was introducedinto a Prototheca moriformis UTEX 1435 genetic background. Twoexpression constructs were created, one with the native Cupheahookeriana C16-preferring thioesterase transit peptide sequence, termedpSZ1417, and a second where the native transit peptide sequence wasreplaced with the transit peptide from C. protothecoides stearoyl-ACPdesaturase (SEQ ID NO: 49), termed pSZ1462. The coding sequence of theC. hookeriana thioesterase with the native transit peptide is listed asSEQ ID NO: 149 and the coding sequence of the C. hookeriana thioesterasewith the replaced transit peptide is listed as SEQ ID NO: 160. Bothexpression constructs contained a 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO:84) homologous recombination targeting sequences (flanking theconstruct) to the 6S genomic region for integration into the nucleargenome and a S. cerevisiae suc2 sucrose invertase coding region underthe control of C. reinhardtii β-tubulin promoter/5′UTR and Chlorellavulgaris nitrate reductase 3′ UTR. This S. cerevisiae suc2 expressioncassette is listed as SEQ ID NO: 159 and served as a selection marker.In both constructs, the C. hookeriana coding region was under thecontrol of the Prototheca moriformis Amt03 promoter/5′UTR (SEQ ID NO:89) and C. vulgaris nitrate reductase 3′UTR. Both constructs weretransformed into a Prototheca moriformis genetic background and positiveclones were screened on plates with sucrose as the sole carbon source. Asubset of the positive clones were selected and grown under lipidproduction conditions and lipid profiles were determined using directtransesterification methods as described above. The lipid profiles ofthe selected clones are summarized in Table 19 below.

TABLE 19 Lipid profiles of Cuphea hookeriana C16:0 preferringthioesterase transgenic Prototheca cells. Strain C10:0 C12:0 C14:0 C16:0C18:0 C18:1 C18:2 wildtype 0.01 0.03 1.17 25.86 2.84 58.33 9.16 pSZ14170.02 0.06 4.21 55.29 2.59 26.87 9.02 clone A pSZ1417 0.02 0.06 4.1254.57 2.31 26.43 10.45 clone B pSZ1417 0.01 0.05 3.59 53.18 2.60 29.029.48 clone C pSZ1462 0.02 0.11 10.62 67.42 2.18 12.95 5.13 clone ApSZ1462 0.03 0.11 8.88 66.83 2.30 15.32 5.16 clone B pSZ1462 0.03 0.119.28 66.65 2.27 15.19 5.14 clone C pSZ1462 0.02 0.09 8.30 66.36 2.2716.52 5.01 clone D

The results show that transformants with either of the Cuphea hookerianaC16:0-preferring thioesterase constructs have significantly impactedC16:0 fatty acid levels and to a lesser extent an impacted C14:0 fattyacid levels, along with a sharp decrease in C18:1 fatty acid levels ascompared to wildtype. The difference in transit peptides in the twoconstructs may account for the increased C16:0 fatty acid levels in thepSZ1462 transformants compared to the pSZ1417 transformants.

Two C16:0-preferring thioesterases from Elaeis guiniensis (African oilpalm) corresponding to the amino acid sequence in Genbank Accession Nos.AAD422220.2 (SEQ ID NO: 152) and ABD83939 (SEQ ID NO: 162), termed E.guiniensis palmitoyl-ACP thioesterase and E. guiniensis palmitoyl-ACPthioesterase PATE, respectively, was introduced into a Protothecamoriformis UTEX 1435 genetic background. The codon-optimized cDNAsequences and amino acid sequences are listed in the Sequence Listing asspecified above. The two thioesterases share a significant level ofamino acid identity (over 94%), but their respective roles in theAfrican oil palm plant is still unclear. The construct encoding the E.guiniensis palmitoyl-ACP thioesterase was termed pSZ1437, and theconstruct encoding the E. guiniensis palmitoyl-ACP thioesterase PATE wastermed pSZ1436. Both expression constructs contained a 5′ (SEQ ID NO:82) and 3′ (SEQ ID NO: 84) homologous recombination targeting sequences(flanking the construct) to the 6S genomic region for integration intothe nuclear genome and a S. cerevisiae suc2 sucrose invertase codingregion under the control of C. reinhardtii β-tubulin promoter/5′UTR andChlorella vulgaris nitrate reductase 3′ UTR. This S. cerevisiae suc2expression cassette is listed as SEQ ID NO: 159 and served as aselection marker. In both constructs, the E. guiniensis thioesterasecoding region was under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR.Both constructs were transformed into a Prototheca moriformis geneticbackground and positive clones were screened on plates with sucrose asthe sole carbon source. A subset of the positive clones were selectedand grown under lipid production conditions and lipid profiles weredetermined using direct transesterification methods as described above.The lipid profiles of the selected clones are summarized in Table 20below.

TABLE 20 Lipid profiles of Elaeis guiniensis C16:0 preferringthioesterase transgenic Prototheca cells. Strain C10:0 C12:0 C14:0 C16:0C18:0 C18:1 C18:2 wildtype 0.01 0.03 1.17 25.86 2.84 58.33 9.16 pSZ14370.02 0.07 3.82 55.86 3.12 24.47 10.48 clone A pSZ1437 0.02 0.05 3.0153.23 3.47 28.70 9.26 clone B pSZ1437 0.02 0.06 3.33 53.20 3.30 26.6411.19 clone C pSZ1437 0.02 0.05 3.08 52.88 3.60 27.94 10.16 clone DpSA1437 0.02 0.05 3.01 52.84 3.48 28.46 9.87 clone E pSZ1436 0.01 0.041.48 29.54 3.33 52.26 10.58 clone A pSZ1436 0.01 0.04 1.48 29.43 3.3352.11 10.76 clone B pSZ1436 0.01 0.04 1.50 29.25 3.38 52.07 10.89 cloneC pSZ1436 0.01 0.04 1.51 29.18 3.41 51.80 11.17 clone D pSZ1436 0.010.04 1.54 29.14 3.56 51.43 11.42 clone E

The E. guiniensis C16:0-preferring thioesterase encoded by pSZ1437 had asignificant impact on the C16:0 fatty acid levels, to a lesser extend,the C14:0 fatty acid levels, and a sharp decrease in the C18:1 fattyacid levels when compared to wildtype. Surprising, the E. guiniensisC16:0-preferring thioesterase PATE encoded by pSZ1436, despite thesignificant level of amino acid identity to the thioesterase encoded bypSZ1436, had relatively little activity with regard to C16:0 or C14:0fatty acid levels.

A C18:0-preferring thioesterase from Brassica napus was introduced intoa Prototheca moriformis UTEX 1435 genetic background, and thecodon-optimized cDNA sequences and amino acid sequences are listed inthe Sequence Listing as specified above. The expression constructcontained a 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologousrecombination targeting sequences (flanking the construct) to the 6Sgenomic region for integration into the nuclear genome and a S.cerevisiae suc2 sucrose invertase coding region under the control of C.reinhardtii β-tubulin promoter/5′UTR and Chlorella vulgaris nitratereductase 3′ UTR. This S. cerevisiae suc2 expression cassette is listedas SEQ ID NO: 159 and served as a selection marker. The B. napus codingregion was under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR.The entire Brassica napus expression cassette was termed pSZ1358 andtransformed into a Prototheca moriformis genetic background. Positiveclones were screened on plates with sucrose as the sole carbon source. Asubset of the positive clones were selected and grown under lipidproduction conditions and lipid profiles were determined using directtransesterification methods as described above. The lipid profiles ofthe selected clones are summarized in Table 21 below.

TABLE 21 Lipid profiles of Brassica napus C18:0-preferring thioesterasetransgenic Prototheca cells. Strain C10:0 C12:0 C14:0 C16:0 C18:0 C18:1C18:2 wildtype 0.00 0.04 1.18 25.44 3.42 57.97 6.98 pSZ1358 0.07 0.311.51 33.27 27.26 27.37 7.50 clone A pSZ1358 0.07 0.33 1.60 34.73 26.7126.52 7.32 clone B

The results show that transformants with the Brassica napusC18:0-preferring thioesterase transgene have significantly impactedC18:0 fatty acid levels and to a lesser extent, impacted C16:0 fattyacid levels, along with a sharp decrease in C18:1 fatty acid levels ascompared to wildtype.

A fatty acyl-ACP thioesterase from Ricinus communis was introduced intoa Prototheca moriformis UTEX 1435 genetic background, and thecodon-optimized cDNA sequences and amino acid sequences are listed inthe Sequence Listing as specified above. The expression constructcontained a 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologousrecombination targeting sequences (flanking the construct) to the 6Sgenomic region for integration into the nuclear genome and a S.cerevisiae suc2 sucrose invertase coding region under the control of C.reinhardtii β-tubulin promoter/5′UTR and Chlorella vulgaris nitratereductase 3′ UTR. This S. cerevisiae suc2 expression cassette is listedas SEQ ID NO: 159 and served as a selection marker. The R. communiscoding region was under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR.The Ricinus communis native transit peptide was also replaced with thetransit peptide from C. protothecoides stearoyl desaturase (SEQ ID NO:49) and the cDNA sequence of the thioesterase with the replaced transitpeptide is listed as SEQ ID NO: 155. The entire Ricinus communisexpression cassette was termed pSZ1375 and transformed into a Protothecamoriformis genetic background. Positive clones were screened on plateswith sucrose as the sole carbon source. A subset of the positive cloneswere selected and grown under lipid production conditions and lipidprofiles were determined using direct transesterification methods asdescribed above. The lipid profiles of the selected clones aresummarized in Table 22 below.

TABLE 22 Lipid profiles of Ricinus communis ACP-thioesterase transgenicPrototheca cells. Strain C10:0 C12:0 C14:0 C16:0 C18:0 C18:1 C18:2wildtype 0.01 0.03 0.98 24.65 3.68 62.48 6.26 pSZ1375 0.01 0.03 0.9118.34 2.55 67.93 8.35 clone A pSZ1375 0.01 0.03 0.97 18.51 2.47 67.838.25 clone B pSZ1375 0.01 0.03 0.93 18.65 2.84 67.58 7.90 clone CpSZ1375 0.01 0.03 0.92 18.90 2.30 67.48 8.37 clone D

The results show that transformants with the Ricinus communisthioesterase transgene have impacted levels of C16:0 fatty acids and toa lesser extent, C18:0 fatty acid levels. Also, there was a concomitantincrease in the C18:1 fatty acid level when compared to the wildtypelevel.

Example 4: Transformation of Prototheca with Multiple ExogenousHeterologous Thioesterase Genes

Microalgae strain Prototheca moriformis (UTEX 1435) was transformedusing the above disclosed methods to express multiple thioesterases in asingle clone. The expression of multiple thioesterases in a single cloneallows the microaglae to produce oils with fatty acid profilescompletely different from those elaborated when any single thioesteraseis expressed alone (as demonstrated in the preceding Examples).Prototheca moriformis (UTEX 1435) was first transformed with theCinnamomum camphora thioesterase (a C14 preferring thioesterase) alongwith a sucrose invertase gene, the suc2 from S. cerevisiae (selectionwas the ability to grow on sucrose) using homologous recombination. TheDNA used for this homologous recombination construct is from the KE858region of Prototheca moriformis genomic DNA as described in the SectionIII above. The relevant portion of this construct is listed in theSequence Listing as SEQ ID NO: 51. Positive clones were screened onsucrose-containing plates. A positive clone was then re-transformed withone of three cassettes, each encoding resistance to the antibiotic G418as well as an additional thioesterase: (1) thioesterase gene from Cupheahookeriana (C8-10 preferring), SEQ ID NO: 52; (2) thioesterase gene fromUmbellularia californica (C12 preferring), SEQ ID NO: 53; orthioesterase from Ulmus americana (broad; C10-C16 preferring), SEQ IDNO: 54. Included in the Sequence Listing is the sequence of the relevantportion of each construct. Clones expressing both thioesterase geneswere screened on sucrose containing medium with 50 μg/ml G418. Positiveclones were selected and growth and lipid profile were assayed. Table 23summarizes the lipid profile of representative positive clones(expressed in Area %).

TABLE 23 Lipid profiles of Prototheca moriformis transformed withmultiple thioesterases. UTEX 1435 + C. camphora TE genetic backgroundFatty UTEX UTEX 1435 + +C. hookeriana +U. californica +U. americana Acid1435 C. camphora TE TE TE TE C8:0 0 0 0.19 0 0.06 C10:0 0.02 0.02 2.160.07 1.87 C12:0 0.05 0.66 0.53 13.55 1.61 C14:0 1.65 10.52 7.64 8.014.58 C16:0 28.0 22.56 22.31 19.98 29.53 C18:0 2.9 6.67 3.23 2.24 2.93C18:1 53.8 47.78 48.54 42.55 37.3 C18:2 10.95 12.3 11.76 10.13 8.9 C18:3α 0.8 0.93 0.91 0.91 0.76 Total 32.62 40.43 36.06 43.84 50.58 saturates(Area %)

Additionally, a double thioesterase clone with C. camphora and U.californica thioesterases was grown in 2% sucrose containing medium with50 mg/L G418 at 22° C. The fatty acid profile obtained from this strainunder these growth conditions was: C8:0 (0); C10:0 (0.10); C12:0(31.03); C14:0 (7.47); C16:0 (15.20); C18:0 (0.90); C18:1 (30.60); C18:2(12.44); and C18:3a (1.38), with a total saturates of 54.7.

Double thioesterase clones with two homologous recombination constructs(one targeting the 6S region and the other targeting the KE858 region)containing the C. camphora thioestease were produced. A positiverepresentative clone had a fatty acid profile of: 0% C8:0; 0.06% C10:0;5.91% C12:0; 43.27% C14:0; 19.63% C16:0; 0.87% C18:0; 13.96% C18:1; and13.78% C18:2, with a total saturates at 69.74%. This clone had a C12-C14level at over 49%, which is over 37 times the C12-C14 level in wildtypecells.

The above data shows that multiple thioesterases can be successfullyco-expressed in microalgae. The co-expression of multiple thioesterasesresults in altered fatty acid profiles that differ significantly notonly from the wild type strain, but also from the fatty acid profileobtained by the expression of any one of the individual thioesterases.The expression of multiple thioesterases with overlapping chain lengthspecificity can result in cumulative increases in those specific fattyacids.

The expression of heterologous thioesterases (either alone or incombination) in Prototheca moriformis not only alters the fattyacid/lipid profiles in the host strain, but when compared to oilscurrently available from a variety of seed crops (Table 5), theseprofiles are of truly unique oils found in no other currently availablesystem. Not only do the transgenic strains show significant differencesfrom the untransformed wildtype strain, they have remarkably differentprofiles from any of the commercial oils that are shown in Table 5. Asan example, both coconut and palm kernel oils have levels of C8-C10fatty acids ranging from 5.5-17%. Transgenic strain expressing the C.palustris C8-preferring thioesterase or the C. hookeriana C10-preferringthioesterase accumulates anywhere from 3.66 to 8.65%, respectively.These C8-C10 fatty acid levels are similar to coconut oil and palmkernel, however, the transgenic algal strains lack the significantlyhigher C12:0 fatty acids, and they have extremely high C16:0 (23% intransgenics versus 11-16% in coconut or palm kernel oil, respectivelyand/or 18:1 (50-57% in transgenics versus-8-19% in coconut or palmkernel oil, respectively.

Generation of Laurate and Myristate Rich Oils in Strain UTEX1435 by theExpression of Cuphea wrightii Thioesterases:

Seeds of Cuphea wrightii have been shown to accumulate oil containingover 25% C10:0 and over 65% C12:0 fatty acids. Two FatB thioesterases,CwFatB1 (Gen Bank Accession no. U56103) and CwFatB2 (Gen Bank Accessionno. U56104), have been cloned from Cuphea wrightii (as described inLeonard et al., Plant Mol. Biol. 34(4):669-79 (1997)) and expressed inArabidopsis thaliana (as described in Leonard et al., Plant J.13(5):621-8 (1998)). Fatty acid profiles of A. thaliana transgenic linesexpressing CwFatB1 and CwFatB2 show increased C12:0 fatty acid speciesup to 16% to 25% (Leonard et al, 1998, supra). Here we demonstrate theability to generate laurate and myristate rich oils by expressing theCuphea wrightii thioesterases, CwFatB1 and CwFatB2, in strain UTEX1435.In the example described here, transgenic strains expressing CwFatB1 andCwFatB2 were generated using the transformation methodology describedbefore.

Amino acid sequences of CwFatB1 and CwFatB2 are shown below with thepredicted chloroplast targeting sequences underlined. These primaryamino acid sequences were used to synthesize the corresponding genes fortransformation constructs. The nucleotide sequences of the two geneswere optimized for expression in strain UTEX 1435 utilizing itspreferred codon usage as previously described.

CwFatB1 (U56103): (SEQ ID NO: 186)MVAAAASSAFFSVPTPGTSPKPGKFGNWPSSLSVPFKPDNGGFVKANASAHPKANGSAVNLKSGSLETPPRSFINQLPDLSMLLSKITTVFGAAEKQWKRPGMLVEPFGVDRIFQDGVFFRQSFSIRSYEIGVDRTASIETLMNIFQETSLNHCKSIGLLNDGFGRTPEMCKRDLIWVVTKIQVEVNRYPTWGDTIEVNTWVSESGKNGMGRDWLISDCRTGEILIRATSVWAMMNQNTRRLSKFPYEVRQEIAPHFVDSAPVIEDDRKLHKLDVKTGDSIRDGLTPRWNDLDVNQHVNNVKYIGWILKSVPIEVFETQELCGVTLEYRRECGRDSVLESVTTMDPAKEGDRCVYQHLLRLEDGADITIGRTEWRPKNAGANGAISSGKTSNGNSVS CwFatB2 (U56104):(SEQ ID NO: 187) MVVAAAASSAFFPVPAPRPTPKPGKFGNWPSSLSQPFKPKSNPNGRFQVKANVSPHPKANGSAVSLKSGSLNTLEDPPSSPPPRTFLNQLPDWSRLRTAITTVFVAAEKQFTRLDRKSKRPDMLVDWFGSETIVQDGLVFRERFSIRSYEIGADRTASIETLMNHLQDTSLNHCKSVGLLNDGFGRTPEMCTRDLIWVLTKMQIVVNRYPTWGDTVEINSWFSQSGKIGMGREWLISDCNTGEILVRATSAWAMMNQKTRRFSKLPCEVRQEIAPHFVDAPPVIEDNDRKLHKFDVKTGDSICKGLTPGWNDFDVNQHVSNVKYIGWILESMPTEVLETQELCSLTLEYRRECGRESVVESVTSMNPSKVGDRSQYQHLLRLEDGADIMKGRTEWRPKNA GTNRAIST

Transformation of UTEX1435 with C. wrightii Thioesterases:

In this example, UTEX 1435 strain was used as the recipient strain intowhich cassettes expressing the C. wrightii FatB1 and FatB2 thioesteraseswere introduced. The transformation constructs contain a cassetteallowing for selection on sucrose (the Saccharomyces cerevesiae suc2gene) along with the thioesterases. Cells were transformed as previouslydescribed using biolistics. Cells were transformed directly on mediacontaining 2% sucrose. Transformation constructs were made such that theexpression of the thioesterases were driven either by the C. reinhardtiiβ-tubulin promoter or by the endogenous UTEX 1435 Amt3 promoter.

Additional versions of the thioesterase cassettes were made in which thenative, higher plant transit peptides were replaced by algal transitpeptides. The transit peptides used in these constructs are designatedas follows: TP1 encodes a transit peptide for Stearoyl ACP desaturasederived from UTEX250; TP2 encodes a transit peptide for Stearoyl ACPdesaturase from derived from UTEX 1435; TP3 encodes a transit peptide ofdelta 12 Fatty Acid desaturase derived from UTEX 1435; and TP4 encodes atransit peptide of isopentenyl diphosphate synthase derived from UTEX1435. The constructs used in this example are listed in Table 24 below.

TABLE 24 TE constructs. Construct Description Const. 16S-CrbTub_suc2_nr::CrbTub_CwFatB1_nr-6S Const. 26S-CrbTub_suc2_nr::CrbTub_CwFatB2_nr-6S Const. 36S-CrbTub_suc2_nr::Amt3_CwFatB1_nr-6S Const. 46S-CrbTub_suc2_nr::Amt3_CwFatB2_nr-6S Const. 56S-CrbTub_suc2_nr::CrbTub_TP1-CwFatB1_nr-6S Const. 66S-CrbTub_suc2_nr::CrbTub_TP2-CwFatB1_nr-6S Const. 76S-CrbTub_suc2_nr::CrbTub_TP3-CwFatB1_nr-6S Const. 86S-CrbTub_suc2_nr::CrbTub_TP4-CwFatB1_nr-6S Const. 96S-CrbTub_suc2_nr::CrbTub_TP1-CwFatB2_nr-6S Const. 106S-CrbTub_suc2_nr::CrbTub_TP2-CwFatB2_nr-6S Const. 116S-CrbTub_suc2_nr::CrbTub_TP3-CwFatB2_nr-6S Const. 126S-CrbTub_suc2_nr::CrbTub_TP4-CwFatB2_nr-6S

Transforming DNA expressing suc2 and the C. wrightii FatB1 thioesterase(Const. 1):

The sequence of the transforming construct,6S-CrbTub_suc2_nr::CrbTub_CwFatB1_nr-6S, designated as Const. 1 is givenbelow. Relevant restriction sites are indicated in lowercase, bold andunderlining and are 5′-3′ SapI, KpnI, AscI, Mfe, BamHI, EcoRI, SpeI,AscI, XhoI, SacI and SapI, respectively. SapI sites delimit the 5′ and3′ ends of the transforming DNA. Underlined sequences at the 5′ and 3′flanks of the construct represent genomic DNA from UTEX1435 that permittargeted integration of the transforming DNA via homologousrecombination (6S region). Proceeding in the 5′ to 3′ direction, the C.reinhardtii β-tubulin promoter driving the expression of S. cerevisiaesuc2 gene (encoding sucrose hydrolyzing activity thereby permitting thestrain to grow on sucrose) is indicated by lowercase, boxed text. Theinitiator ATG and terminator TGA for suc2 are indicated by uppercase,bold italics while the coding region is indicated in lowercase italics.The Chlorella vulgaris nitrate reductase 3′ UTR is indicated bylowercase bold text followed by a spacer region. The C. reinhardtiiβ-tubulin promoter, driving expression of the C. wrightii TE (CwFatB1)is indicated by boxed text. The initiator ATG and terminator TGA of thethioesterase (CwFatB1) are indicated in uppercase, bold italicized textwhile the remainder of the coding region is indicated in lowercaseitalics. The predicted plastid targeting sequence of the thioesteraselies between the initiator ATG and the AscI site in the sequence. The C.vulgaris nitrate reductase 3′UTR is indicated by bold text.

Constuct 1: (SEQ ID NO: 188)gctcttcgccgccgccactcctgctcgagcgcgcccgcgcgtgcgccgccagcgccttggccttttcgccgcgctcgtgcgcgtcgctgatgtccatcaccaggtccatgaggtctgccttgcgccggctgagccactgcttcgtccgggcggccaagaggagcatgagggaggactcctggtccagggtcctgacgtggtcgcggctctgggagcgggccagcatcatctggctctgccgcaccgaggccgcctccaactggtcctccagcagccgcagtcgccgccgaccctggcagaggaagacaggtgaggggggtatgaattgtacagaacaaccacgagccttgtctaggcagaatccctaccagtcatggctttacctggatgacggcctgcgaacagctgtccagcgaccctcgctgccgccgcttctcccgcacgcttctttccagcaccgtgatggcgcgagccagcgccgcacgctggcgctgcgcttcgccgatctgaggacagtcggggaactctgatcagtctaaacccccttgcgcgttagtgttgccatcctttgcagaccggtgagagccgacttgttgtgcgccaccccccacaccacctcctcccagaccaattctgtcacctttttggcgaaggcatcggcctcggcctgcagagaggacagcagtgcccagcc

accgccccctggtgcacttcacccccaacaagggctggatgaacgaccccaacggcctgtggtacgacgagaaggacgccaagtggcacctgtacttccagtacaacccgaacgacaccgtctgggggacgcccttgttctggggccacgccacgtccgacgacctgaccaactgggaggaccagcccatcgccatcgccccgaagcgcaacgactccggcgccttctccggctccatggtggtggactacaacaacacctccggcttcttcaacgacaccatcgacccgcgccagcgctgcgtggccatctggacctacaacaccccggagtccgaggagcagtacatctcctacagcctggacggcggctacaccttcaccgagtaccagaagaaccccgtgctggccgccaactccacccagttccgcgacccgaaggtcttctggtacgagccctcccagaagtggatcatgaccgcggccaagtcccaggactacaagatcgagatctactcctccgacgacctgaagtcctggaagctggagtccgcgttcgccaacgagggcttcctcggctaccagtacgagtgccccggcctgatcgaggtccccaccgagcaggaccccagcaagtcctactgggtgatgttcatctccatcaaccccggcgccccggccggcggctccttcaaccagtacttcgtcggcagcttcaacggcacccacttcgaggccttcgacaaccagtcccgcgtggtggacttcggcaaggactactacgccctgcagaccttcttcaacaccgacccgacctacgggagcgccctgggcatcgcgtgggcctccaactgggagtactccgccttcgtgcccaccaacccctggcgctcctccatgtccctcgtgcgcaagttctccctcaacaccgagtaccaggccaacccggagacggagctgatcaacctgaaggccgagccgatcctgaacatcagcaacgccggcccctggagccggttcgccaccaacaccacgttgacgaaggccaacagctacaacgtcgacctgtccaacagcaccggcaccctggagttcgagctggtgtacgccgtcaacaccacccagacgatctccaagtccgtgttcgcggacctctccctctggttcaagggcctggaggaccccgaggagtacctccgcatgggcttcgaggtgtccgcgtcctccttcttcctggaccgcgggaacagcaaggtgaagttcgtgaaggagaacccctacttcaccaaccgcatgagcgtgaacaaccagcccttcaagagcgagaacgacctgtcctactacaaggtgtacggcttgctggaccagaacatcctggagctgtacttcaacgacggcgacgtcgtgtccaccaacacctacttcatgaccaccgggaacgccctgggctccgtgaacatgacgacgggggtggacaacctgttctacatcgacaagttccaggtgcgcgaggtcaag

gccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatgga ggatcccgcgtctcgaacagagcgcgcagaggaacgctgaaggtctcgcctctgtcgcacctcagcgcggcatacaccacaataaccacctgacgaatgcgcttggttcttcgtccattagcgaagcgtccggttcacacacgtgccacgttggcgaggtggcaggtgacaatgatcggtggagctgatggt

gcccagcagcctgagcgtgcccttcaagcccgacaacggcggcttccacgtgaaggccaacgccagcgcccacgggcgcgcccccaaggccaacggcagcgccgtgaacctgaagtccggcagcctggagacccccccccgcagcttcatcaaccagctgcccgacctgagcatgctgctgagcaagatcaccaccgtgttcggcgccgccgagaagcagtggaagcgccccggcatgctggtggagcccttcggcgtggaccgcatcttccaggacggcgtgttcttccgccagagcttcagcatccgcagctacgagatcggcgtggaccgcaccgccagcatcgagaccctgatgaacatcttccaggagaccagcctgaaccactgcaagagcatcggcctgctgaacgacggcttcggccgcacccccgagatgtgcaagcgcgacctgatctgggtggtgaccaagatccaggtggaggtgaaccgctaccccacctggggcgacaccatcgaggtgaacacctgggtgagcgagagcggcaagaacggcatgggccgcgactggctgatcagcgactgccgcaccggcgagatcctgatccgcgccaccagcgtgtgggccatgatgaaccagaacacccgccgcctgagcaagttcccctacgaggtgcgccaggagatcgccccccacttcgtggacagcgcccccgtgatcgaggacgaccgcaagctgcacaagctggacgtgaagaccggcgacagcatccgcgacggcctgaccccccgctggaacgacctggacgtgaaccagcacgtgaacaacgtgaagtacatcggctggattctgaagtccgtgcccatcgaggtgttcgagacccaggagctgtgcggcgtgaccctggagtaccgccgcgagtgcggccgcgacagcgtgctggagagcgtgaccaccatggaccccgccaaggagggcgaccgctgcgtgtaccagcacctgctgcgcctggaggacggcgccgacatcaccatcggccgcaccgagtggcgccccaagaacgccggcgccaacg

atcgacacactctggacgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaaagcttgagctcttgttttccagaaggagttgctccttgagcctttcattctcagcctcgataacctccaaagccgctctaattgtggagggggttcgaatttaaaagcttggaatgttggttcgtgcgtctggaacaagcccagacttgttgctcactgggaaaaggaccatcagctccaaaaaacttgccgctcaaaccgcgtacctctgctttcgcgcaatctgccctgttgaaatcgccaccacattcatattgtgacgcttgagcagtctgtaattgcctcagaatgtggaatcatctgccccctgtgcgagcccatgccaggcatgtcgcgggcgaggacacccgccactcgtacagcagaccattatgctacctcacaatagttcataacagtgaccatatttctcgaagctccccaacgagcacctccatgctctgagtggccaccccccggccctggtgcttgcggagggcaggtcaaccggcatggggctaccgaaatccccgaccggatcccaccacccccgcgatgggaagaatctctccccgggatgtgggcccaccaccagcacaacctgtccgaagcaggggttgctagggatcgctccgagtccgcaaacccttgtcgcgtggcggggcttgttcgagcttgaagagc

Transforming DNA Expressing Suc2 and the C. wrightii FatB2 Thioesterase(Const. 2):

The transforming construct, 6S-CrbTub_suc2_nr::CrbTub_CwFatB2_nr-6S,designated as Const. 2, was generated by replacing the CwFatB1 gene fromConst. 1 with the codon optimized CwFatB2 gene utilizing the SpeI andAscI restriction sites, which are indicated in lowercase, in bold andunderlined. The initiator ATG and terminator TGA of the thioesterase(CwFatB2) are indicated in uppercase, bold italicized text while theremainder of the coding region is indicated in lowercase italics. Thepredicted plastid targeting sequence of the thioesterase lies betweenthe initiator ATG and the AscI site in the sequence.

Construct 2 (partial): (SEQ ID NO: 189) actagt

gtggtggccgccgccgccagcagcgccttcttccccgtgcccgccccccgccccacccccaagcccggcaagttcggcaactggcccagcagcctgagccagcccttcaagcccaagagcaaccccaacggccgcttccaggtgaaggccaacgtgagcccccacg

cccaaggccaacggcagcg ccgtgagcctgaagtccggcagcctgaacaccctggaggacccccccagcagcccccccccccgcaccttcctgaaccagctgcccgactggagccgcctgcgcaccgccatcaccaccgtgttcgtggccgccgagaagcagttcacccgcctggaccgcaagagcaagcgccccgacatgctggtggactggttcggcagcgagaccatcgtgcaggacggcctggtgttccgcgagcgcttcagcatccgcagctacgagatcggcgccgaccgcaccgccagcatcgagaccctgatgaaccacctgcaggacaccagcctgaaccactgcaagagcgtgggcctgctgaacgacggcttcggccgcacccccgagatgtgcacccgcgacctgatctgggtgctgaccaagatgcagatcgtggtgaaccgctaccccacctggggcgacaccgtggagatcaacagctggttcagccagagcggcaagatcggcatgggccgcgagtggctgatcagcgactgcaacaccggcgagatcctggtgcgcgccaccagcgcctgggccatgatgaaccagaagacccgccgcttcagcaagctgccctgcgaggtgcgccaggagatcgccccccacttcgtggacgccccccccgtgatcgaggacaacgaccgcaagctgcacaagttcgacgtgaagaccggcgacagcatctgcaagggcctgacccccggctggaacgacttcgacgtgaaccagcacgtgagcaacgtgaagtacatcggctggattctggagagcatgcccaccgaggtgctggagacccaggagctgtgcagcctgaccctggagtaccgccgcgagtgcggccgcgagagcgtggtggagagcgtgaccagcatgaaccccagcaaggtgggcgaccgcagccagtaccagcacctgctgcgcctggaggacggcgccgacatcatgaagggccgcaccgagtggcgccccaagaacgccggcacca accgcgccatcagcacc

ttaattaa ctcgag

Transforming DNA expressing suc2 and the C. wrightii FatB1 and FatB2thioesterases driven by amt3 promoter (Const. 3 & 4):

The transforming constructs 6S-CrbTub_suc2_nr::Amt3_CwFatB1_nr-6S,designated as Const. 3, and 6S-CrbTub_suc2_nr::Amt3_CwFatB2_nr-6S,designated as Const. 4 were generated by replacing the CrbTub promoterdriving the thioesterases, from Const. 1 and Const. 2, with the Amt3promoter derived from UTEX1435 as an EcoRI and SpeI restrictionfragment, indicated below in lowercase, bold and underlined. The Amt3promoter region is indicated by lowercase boxed text.

Constructs 3 and 4 (partial): (SEQ ID NO: 190)

Transforming DNA Expressing C. wrightii FatB1 Thioesterase Under theControl of Algal Transit Peptides:

The transforming constructs 6S-CrbTub_suc2_nr::CrbTub_TP1-CwFatB1_nr-6S,designated as Const. 5; construct6S-CrbTub_suc2_nr::CrbTub_TP2-CwFatB1_nr-6S, designated as Const. 6;construct 6S-CrbTub_suc2_nr::CrbTub_TP3-CwFatB1_nr-6S, designated asConst. 7 and construct 6S-CrbTub_suc2_nr::CrbTub_TP4-CwFatB1_nr-6S,designated as Const. 8 were generated by replacing the native transitpeptide of CwFatB1 from Const. 1 with the corresponding algal transitpeptides shown below as SpeI and AscI restriction fragments, which areindicated in lowercase, bold and underlining. The resulting algaltransit peptide sequences lie between the initiator ATG and the AscIsite in the sequences below.

Constructs 5-12 (partial): TP1 (UTEX250 Stearoyl ACP Desaturase transitpeptide sequence) (SEQ ID NO: 191) actagt

gccaccgcatccactttctcggcgttcaatgcccgctgcggcgacctgcgtcgctcggcgggctccgggccccggcgcccagcgaggcc cctccccgtgcgcgggcgcgcc TP2 (UTEX1435 Stearoyl ACP Desaturase transit peptide sequence)(SEQ ID NO: 192) actagt

gcttccgcggcattcaccatgtcggcgtgccccgcgatgactggcagggcccctggggcacgtcgctccggacggccagtcgccacccg cctgaggg ggcgcgccTP3 (UTEX1435 Deltal2 Fatty Acid Desaturase transit peptide sequence)(SEQ ID NO: 193) actagt

gctatcaagacgaacaggcagcctgtggagaagcctccgttcacgatcgggacgctgcgcaaggccatccccgcgcactgtttcgagcg ctcggcgcttcgtgggcgcgcc TP4 (UTEX1435 Isopentenyl Diphospate Synthasetransit peptide sequence) (SEQ ID NO: 194) actagt

acgttcggggtcgccctcccggccatgggccgcggtgtctcccttccccggcccagggtcgcggtgcgcgcccagtcggcgagtcaggt tttggagagcg ggcgcgcc

Transforming DNA expressing C. wrightii FatB2 thioesterase under thecontrol of algal transit peptides: The transforming constructs6S-CrbTub_suc2_nr::CrbTub_TP1-CwFatB2_nr-6S, designated as Const. 9;construct 6S-CrbTub_suc2_nr::CrbTub_TP2-CwFatB2_nr-6S, designated asConst. 10; construct 6S-CrbTub_suc2_nr::CrbTub_TP3-CwFatB2_nr-6S,designated as Const. 11 and construct6S-CrbTub_suc2_nr::CrbTub_TP4-CwFatB2_nr-6S, designated as Const. 12were generated by replacing the native transit peptide of CwFatB2 fromConst. 2 with the corresponding algal transit peptides shown above asSpeI and AscI restriction fragments, which are indicated in lowercase,bold and underlining. The algal transit peptide sequence lies betweenthe initiator ATG and the AscI site in the sequences above.

Fatty Acid Profiles Resulting from Strains Expressing Cuphea wrightiiThioesterases:

Strains transformed with the constructs described above were grown underconditions allowing for the production of oil as previously described.Wild type UTEX 1435 was grown on glucose while all the transgenic linesgenerated by transformation of UTEX 1435 were grown on sucrose. For eachconstruct tested, four transformants were analyzed for impacts on fattyacid profiles. The fatty acid profiles for transgenic strains are shownin Tables 25 to 28 below.

Transgenic lines of A. thaliana expressing CwFatB1 and CwFatB2 (Table25) show a significant impact on the accumulation of C16:0 fatty acidsalong with accumulation of C14:0 and C12:0 fatty acids (from Leonard etal, 1998, supra).

As can be seen from Table 26, transgenic UTEX 1435 lines expressingCwFatB1 (Const. 1 & Const. 3) with the native, higher plant transitpeptide, show an impact primarily on C14:0 fatty acid accumulation andto a lesser extent on C12:0 fatty acid accumulation. The transgenicUTEX1435 lines expressing CwFatB2 (Const. 2 & Const. 4) with the nativehigher plant transit peptide, show significant impact on C12:0 and C14:0fatty acid accumulation, with the impact on C12:0 being higher than onC14:0. A comparison between the two promoters, CrbTub (Const. 1 & Const.2) and Amt3 (Const. 3 & Const. 4) demonstrates that transgenic linesexpressing CwFatB1 & CwFatB2 show significantly higher impacts on C10:0,C12:0, C14:0 and C16:0 fatty acids when driven by the Amt3 promoter.

Analysis of transgenic lines wherein the expression of CwFatB1thioesterase is driven by the four different algal chloroplast targetingsequences (Const. 5, 6, 7, and 8) shows that any of the algal transitpeptides targets the thioesterase to the plastid more efficiently thanthe native higher plant transit peptide (compare the C12:0 and C14:0levels in constructs 5-8, Table 27, with those in construct 1, Table26). Further analysis of these transgenic lines reveals that of the fouralgal transit peptides TP2 (UTEX1435 Stearoyl ACP Desaturase chloroplasttargeting sequence) and TP3 (UTEX 1435 Delta 12 Fatty Acid Desaturasechloroplast targeting sequence) show a greater impact on C12:0 and C14:0accumulation. It appears that these two transit peptides (TP1 & TP2) arebetter at targeting the CwFatB1 to the plastid in UTEX 1435.

Analysis of transgenic lines wherein the expression of CwFatB2thioesterase is driven by the four different algal chloroplast targetingsequences (Const. 9, 10, 11, and 12) demonstrates that only one of thealgal transit peptides gives superior performance to the native, higherplant transit peptide, namely TP-1, as can be seen higher impact on theC12:0 and C14:0 fatty acids (compare Const 9 to Const. 2).

The impact of these C. wrightii thioesterases when expressed in UTEX1435 is significantly different than when expressed in Arabidopsis.Transgenic lines of A. thaliana expressing CwFatB1 and CwFatB2 (Table25) show a significant impact on the accumulation of C16:0 fatty acidsalong with accumulation of C14:0 and C12:0 fatty acids. CwFatB1 andCwFatB2 expressed in UTEX 1435, however, do not show the same level ofimpact on C16:0 fatty acids. The C12:C14 ratios in all the UTEX 1435transgenic lines, expressing CwFatB1, and some expressing CwFatB2(Const. 10, 11, 12) are similar to the A. thaliana transgenic linesexpressing this thioesterase (Table 29). However, the UTEX 1435transgenic lines show a significantly lower C14:C16 ratio compared tothe A. thaliana transgenic lines (Table 29). The C12:C14 and C14:C16ratios in the UTEX 1435 transgenic lines generated with Const. 2, 4, 9are significantly different than the A. thaliana transgenic linesexpressing the same thioesterase (Table 29). Thus, the expression ofCwFatB1 and CwFatB2, in UTEX 1435 generated an oil profile that issignificantly different than that generated in transgenic lines ofArabidopsis expressing the same thioesterases. The oil profile in theseUTEX 1435 transgenic lines is also distinctly different from that inwild type UTEX 1435.

Finally, the modified oils produced by the transgenic lines described inthis Example are also significantly different than the laurate rich oilsgenerated in transgenic UTEX 1435 lines expressing a C12:0 specificthioesterase from Umbellularia californica (described previously).

Taken together, these data indicate that: (1) expression of Cupheawrightii thioesterases in UTEX 1435 has a significant impact on fattyacid profiles and generates unique oils; (2) the expression of CwFatB1thioesterase in the strain UTEX 1435 results in the generation of an oilrich in myristate; (3) the expression of CwFatB2 thioestease in UTEX1435 results in the generation of an oil rich in both laurate andmyristate; and (4) the expression of CwFatB1 and FatB2 in algaegenerates profiles quite distinct from those generated in a model higherplant system, both in terms of the absolute levels of mid-chain fattyacids produced and in their relative ratios to one another.

TABLE 25 Fatty acid profiles (expressed as area %) in UTEX1435, A.thaliana wild type (Ath) and A. thaliana transgenic lines expressingCwFatB1 (CwFatB1-Ath) and CwFatB2 (CwFatB2-Ath) thioesterases. Sample IDC10:0 C12:0 C14:0 C16:0 C18:0 C18:1 C18:2 C18:3 C20:0 C20:1 UTEX14350.01 0.03 0.93 23.83 3.27 61.85 8.08 0.53 0.31 0.08 Ath 0.00 0.00 0.008.40 3.80 13.00 29.20 20.10 2.40 19.30 CwFatB1-Ath 0.00 7.10 24.40 22.803.30 4.50 14.10 12.90 3.00 6.00 CwFatB2-Ath 4.40 16.40 15.30 18.10 3.904.90 13.90 13.60 2.80 5.70

TABLE 26 Fatty acid profiles (expressed as area %) in UTEX1435transgenic lines expressing Const. 1; Const. 2; Const. 3 and Const. 4.Construct Sample ID C10:0 C12:0 C14:0 C16:0 C18:0 C18:1 C18:2 C18:3C20:0 C20:1 Const. 1 1A 0.01 0.43 3.17 19.84 1.66 60.34 12.38 0.45 0.230.02 1B 0.01 0.52 3.45 19.81 2.03 60.65 11.42 0.42 0.26 0.02 1C 0.010.59 3.62 20.53 2.24 59.64 11.29 0.42 0.26 0.02 1D 0.01 0.67 3.92 21.971.96 58.62 10.82 0.44 0.24 0.02 Const. 2 2A 0.63 7.47 5.64 18.74 2.3652.11 10.98 0.49 0.28 0.02 2B 0.82 7.77 5.83 19.84 2.62 51.98 9.24 0.500.24 0.02 2C 0.82 9.57 6.31 18.64 1.66 50.89 10.42 0.43 0.21 0.01 2D0.90 10.04 7.11 17.99 2.34 49.03 10.63 0.47 0.26 0.02 Const. 3 3A 0.042.85 12.09 28.04 2.69 39.02 12.35 1.05 0.25 0.05 3B 0.03 2.90 13.3928.01 2.02 41.47 10.01 0.71 0.21 0.05 3C 0.04 3.30 14.10 27.91 2.0940.50 9.92 0.71 0.21 0.04 3D 0.04 3.71 15.10 27.88 2.01 39.56 9.62 0.680.21 0.06 Const. 4 4A 1.43 11.78 8.87 19.67 2.04 43.80 10.28 0.77 0.210.06 4B 1.39 12.26 9.29 16.88 1.48 44.20 12.18 0.86 0.19 0.08 4C 1.7313.42 9.55 18.93 2.05 41.92 10.30 0.81 0.21 0.04 4D 1.82 14.18 10.0718.56 1.93 41.22 10.21 0.78 0.19 0.05

TABLE 27 Fatty acid profiles (expressed as area %) in UTEX1435transgenic lines expressing Const. 5; Const. 6; Const. 7 and Const. 8.Construct Sample ID C10:0 C12:0 C14:0 C16:0 C18:0 C18:1 C18:2 C18:3C20:0 C20:1 Const. 5 5A 0.02 0.62 4.33 23.30 2.00 57.43 10.00 0.59 0.260.09 5B 0.02 0.78 5.11 25.06 2.45 55.65 8.76 0.58 0.26 0.07 5C 0.02 1.207.41 24.48 1.87 52.65 10.18 0.60 0.24 0.08 5D 0.02 1.33 7.56 24.55 1.8752.59 9.90 0.54 0.26 0.09 Const. 6 6A 0.02 0.56 4.01 24.23 2.50 57.049.32 0.57 0.28 0.08 6B 0.02 0.69 4.97 23.41 1.92 55.59 10.98 0.61 0.250.09 6C 0.02 1.14 7.07 25.05 2.11 53.23 9.23 0.60 0.23 0.07 6D 0.05 5.1019.88 21.43 1.29 40.40 9.89 0.63 0.20 0.08 Const. 7 7A 0.02 1.39 8.3625.39 2.00 51.37 9.37 0.55 0.22 0.07 7B 0.02 1.42 7.59 24.77 2.12 53.178.87 0.47 0.23 0.08 7C 0.02 1.49 7.82 24.87 2.10 52.45 9.14 0.53 0.240.08 7D 0.03 2.15 11.01 25.64 1.85 47.35 9.92 0.51 0.23 0.08 Const. 8 8A0.02 0.81 5.28 23.38 2.03 56.10 10.14 0.54 0.26 0.09 8B 0.02 0.88 5.7723.58 1.91 54.91 10.58 0.57 0.24 0.09 8C 0.02 1.27 7.57 24.28 1.93 52.959.88 0.54 0.24 0.08 8D 0.02 1.43 5.02 21.52 2.63 58.32 9.14 0.52 0.280.09

TABLE 28 Fatty acid profiles (expressed as area %) in UTEX1435transgenic lines expressing Const. 9; Const. 10; Const. 11 and Const.12. Construct Sample ID C10:0 C12:0 C14:0 C16:0 C18:0 C18:1 C18:2 C18:3C20:0 C20:1 Const. 9 9A 0.90 8.96 6.59 19.24 2.20 51.17 8.91 0.56 0.240.08 9B 1.00 9.07 6.31 19.55 2.21 51.43 8.47 0.53 0.25 0.07 9C 1.0612.08 8.79 17.57 1.70 46.54 10.29 0.58 0.21 0.07 9D 1.27 13.05 8.6717.70 1.78 46.28 9.38 0.57 0.22 0.07 Const. 10 10A 0.52 5.55 5.00 20.602.03 53.35 10.66 0.71 0.24 0.07 10B 0.53 5.76 5.16 20.63 1.92 52.8010.90 0.67 0.23 0.06 10C 0.47 5.86 5.20 19.54 1.89 53.34 11.41 0.62 0.260.06 10D 0.87 8.59 6.85 19.65 1.98 49.65 10.21 0.69 0.23 0.08 Const. 1111A 0.21 2.48 2.85 20.80 1.99 57.69 11.53 0.70 0.27 0.11 11B 0.22 2.803.01 21.30 1.89 57.28 11.07 0.66 0.27 0.11 11C 0.29 3.22 3.38 21.33 2.0956.92 10.42 0.71 0.25 0.05 11D 0.28 4.01 4.01 18.79 1.69 56.08 12.730.64 0.26 0.09 Const. 12 12A 0.65 6.01 5.43 21.50 2.10 52.70 9.28 0.750.24 0.10 12B 0.52 6.58 5.62 18.71 1.78 52.59 11.84 0.66 0.26 0.11 12C0.78 8.60 6.88 19.01 1.69 50.40 10.45 0.69 0.23 0.08 12D 0.72 8.75 7.0717.74 1.54 50.57 11.29 0.68 0.22 0.10

TABLE 29 Ratios of C12:C14 and C14:C16in UTEX1435 transgenic linesexpressing CwFatB1 (Const. 1, 3, 5, 6, 7, 8) and CwFatB2 (Const. 2, 4,9, 10, 11, 12) along with A. thaliana transgenic lines expressingCwFatB1 (CwFatB1-Ath) and CwFatB2 (CwFatB2-Ath). Sample ID Average 12:14ratio Average 14:16 ratio CwFatB1-Ath 0.291 1.070 Const. 1 0.155 0.172Const. 3 0.233 0.489 Const. 5 0.250 0.250 Const. 6 0.174 0.397 Const. 70.185 0.345 Const. 8 0.190 0.254 CwFatB2-Ath 1.072 0.845 Const. 2 1.3960.332 Const. 4 1.365 0.512 Const. 9 1.419 0.414 Const. 10 1.152 0.277Const. 11 0.938 0.163 Const. 12 1.191 0.328

Example 5: Identification of Endogenous Nitrogen-Dependent ProtothecaPromoters

A. Identification and Characterization of Endogenous Nitrogen-DependentPromoters.

A cDNA library was generated from Prototheca moriformis (UTEX 1435)using standard techniques. The Prototheca moriformis cells were grownfor 48 hours under nitrogen replete conditions. Then a 5% innoculum(v/v) was then transferred to low nitrogen and the cells were harvestedevery 24 hours for seven days. After about 24 hours in culture, thenitrogen supply in the media was completely depleted. The collectedsamples were immediately frozen using dry ice and isopropanol. Total RNAwas subsequently isolated from the frozen cell pellet samples and aportion from each sample was held in reserve for RT-PCR studies. Therest of the total RNA harvested from the samples was subjected to polyAselection. Equimolar amounts of polyA selected RNA from each conditionwas then pooled and used to generate a cDNA library in vector pcDNA 3.0(Invitrogen). Roughly 1200 clones were randomly picked from theresulting pooled cDNA library and subjected to sequencing on bothstrands. Approximately 68 different cDNAs were selected from among these1200 sequences and used to design cDNA-specific primers for use inreal-time RT-PCR studies.

RNA isolated from the cell pellet samples that were held in reserve wasused as substrate in the real time RT-PCR studies using thecDNA-specific primer sets generated above. This reserved RNA wasconverted into cDNA and used as substrate for RT-PCR for each of the 68gene specific primer sets. Threshold cycle or C_(T) numbers were used toindicate relative transcript abundance for each of the 68 cDNAs withineach RNA sample collected throughout the time course. cDNAs showingsignificant increase (greater than three fold) between nitrogen repleteand nitrogen-depleted conditions were flagged as potential genes whoseexpression was up-regulated by nitrogen depletion. As discussed in thespecification, nitrogen depletion/limitation is a known inducer oflipogenesis in oleaginous microorganisms.

In order to identify putative promoters/5′UTR sequences from the cDNAswhose expression was upregulated during nitrogen depletion/limitation,total DNA was isolated from Prototheca moriformis (UTEX 1435) grownunder nitrogen replete conditions and were then subjected to sequencingusing 454 sequencing technology (Roche). cDNAs flagged as beingup-regulated by the RT-PCR results above were compared using BLASTagainst assembled contigs arising from the 454 genomic sequencing reads.The 5′ ends of cDNAs were mapped to specific contigs, and wherepossible, greater than 500 bp of 5′ flanking DNA was used to putativelyidentify promoters/UTRs. The presence of promoters/5′UTR weresubsequently confirmed and cloned using PCR amplification of genomicDNA. Individual cDNA 5′ ends were used to design 3′ primers and 5′ endof the 454 contig assemblies were used to design 5′ gene-specificprimers.

As a first screen, one of the putative promoter, the 5′UTR/promoterisolated from Aat2 (Ammonium transporter, SEQ ID NO: 63), was clonedinto the Cinnamomum camphora C14 thioesterase construct with theChlorella protothecoides stearoyl ACP desaturase transit peptide,replacing the C. sorokinana glutamate dehydrogenase promoter. Thisconstruct is listed as SEQ ID NO: 81. To test the putative promoter, thethioesterase construct is transformed into Prototheca moriformis cellsto confirm actual promoter activity by screening for an increase inC14/C12 fatty acids under low/no nitrogen conditions, using the methodsdescribed above. Similar testing of the putative nitrogen-regulatedpromoters isolated from the cDNA/genomic screen can be done using thesame methods.

Other putative nitrogen-regulated promoters/5′UTRs that were isolatedfrom the cDNA/genomic screen were:

Promoter/5′UTR SEQ ID NO. Fold increased FatB/A promoter/5′UTR SEQ IDNO: 55 n/a NRAMP metal transporter promoter/5′UTR SEQ ID NO: 56 9.65Flap Flagellar-associated protein promoter/5′UTR SEQ ID NO: 57 4.92SulfRed Sulfite reductase promoter/5′UTR SEQ ID NO: 58 10.91 SugT Sugartransporter promoter/5′UTR SEQ ID NO: 59 17.35 Amt03-Ammoniumtransporter 03 promoter/5′UTR SEQ ID NO: 60 10.1 Amt02-Ammoniumtransporter 02 promoter/5′UTR SEQ ID NO: 61 10.76 Aat01-Amino acidtransporter 01 promoter/5′UTR SEQ ID NO: 62 6.21 Aat02-Amino acidtransporter 02 promoter/5′UTR SEQ ID NO: 63 6.5 Aat03-Amino acidtransporter 03 promoter/5′UTR SEQ ID NO: 64 7.87 Aat04-Amino acidtransporter 04 promoter/5′UTR SEQ ID NO: 65 10.95 Aat05-Amino acidtransporter 05 promoter/5′UTR SEQ ID NO: 66 6.71

Fold increase refers to the fold increase in cDNA abundance after 24hours of culture in low nitrogen medium.

To gain further insight into potential regulation of these putativepromoter/5′UTRs, eight of the sequences were selected for furthertesting: (1) FatB/A; (2) SulfRed Sulfite reductase; (3) SugT Sugartransporter; (4) Amt02-Ammonium transporter 02; (5) Aat01-Amino acidtransporter 01; (6) Aat03-Amino acid transporter 03; (7) Aat04-Aminoacid transporter 04; and (8) Aat05-Amino acid transporter 05. Higherresolution transcriptome analysis utilizing Illumina sequencing readswere carried out on RNA isolated from Prototheca moriformis cellsvarious time points: T0 (seed); 20 hours; 32 hours; 48 hours; 62 hours;and 114 hours post inoculation from seed. The medium at T0 (seed) wasnitrogen replete, while at the time points 20 hours and longer, themedium contained little to no nitrogen. Assembled transcript contigsgenerated from RNA isolated from each of the time points were thenblasted independently with each of the eight previously identifiedtranscripts. The results are summarized in Table 30 below.

TABLE 30 Transcriptome expression profiles for eight putativepromoters/5′UTRs. cDNA TS T20 T32 T48 T62 T114 aa trans_01 absolute 9896 321 745 927 1300 relative 1 0.98 3.28 7.61 9.47 13.28 aa trans_03absolute 7 21 51 137 102 109 relative 1 2.95 7.2 19.42 14.47 15.45 aatrans_04 absolute 1 6 25 90 131 160 relative 1 5.16 21.29 74.97 109.35133.31 aa trans_05 absolute 109 88 123 210 214 273 relative 1 0.81 1.131.93 1.97 2.51 ammon trans_02 absolute 683 173 402 991 1413 1397relative 1 0.25 0.59 1.45 2.07 2.04 fatA/B-1_cDNA absolute 13 36 654 617544 749 relative 1 2.8 51.57 48.65 42.9 59.1 sug trans_01 absolute 25 25106 261 266 251 relative 1 1 4.22 10.4 10.63 10 sulfite reductase_01absolute 634 238 138 145 163 155 relative 1 0.38 0.22 0.22 0.26 0.24

From the above-summarized results, several of the transcripts showincreased accumulation over time, although interestingly, the sulfitereductase mRNA shows a distinct decrease in mRNA accumulation over time.

These eight putative promoter/5′UTR regions were cloned upstream of theC. camphora thioesterase coding region with its native transit peptidetaken out and substituted with the transit peptide from Chlorellaprotothecoides (UTEX 250) stearoyl ACP desaturase. Each putativepromoter/5′UTR region construct was introduced into Protothecamoriformis UTEX 1435 via homologous recombination using DNA from the 6Sgenomic sequence. Also contained within the construct is a suc2 sucroseinvertase gene from S. cerevisiae for selection of positive clones onsucrose containing media/plates. The cDNA sequence for the relevantportions of the construct for Aat01 is listed in the Sequence Listing asSEQ ID NO: 67. For the other constructs, the same backbone was use, theonly variable was the putative promoter/5′UTR sequence. An additionalcontrol transgenic strain was generated in which the C. reinhardtii betatubulin promoter was used to drive expression of the C. camphorathioesterase gene. This promoter have shown to drive constitutiveexpression of the gene of interest, and thus provides a useful controlagainst which to measure expression of the same thioesterase messagewhen driven by the various putative N-regulated promoters/5′UTRs tested.

Once the transgenic clones were generated, three separate experimentswere carried out. The first two experiments assess the potentialnitrogen regulatability of all eight putative promoters by measuringsteady state thioesterase mRNA levels via RT-PCR, fatty acid profilesand ammonia levels in the culture supernatants. Clones were initiallygrown at 28° C. with agitation (200 rpm) in nitrogen rich seed medium (1g/L ammonium nitrate-15 mM nitrogen as ammonia, 4 g/L yeast extract) for24 to 48 hours, at which point 20 OD units (A₇₅₀) were used to inoculate50 ml of low nitrogen media (0.2 g/L ammonium sulfate-3 mM nitrogen asammonia, 0.2 g/L yeast extract). Cells were sampled every 24 hours for 6days and a sample was also collected right before switching to lownitrogen conditions. A portion of the cells from each sample was thenused for total RNA extraction using Trizol reagent (according tomanufacturer's suggested methods). Ammonia assays revealed that ammonialevels in the supernatants fell below the limits of detection (˜100 μM)after 24 hours in low nitrogen medium.

For real-time RT-PCR, all RNA levels were normalized to levels of aninternal control RNA expressed in Prototheca moriformis (UTEX 1435) foreach time point. The internal control RNA, termed cd189, is a product ofthe ARG9 gene which encodes N-acetyl ornithine aminotransferase. Primerssets used for real-time RT-PCR in these experiments were:

Gene specific to Primer sequence 5′-3′ SEQ ID NO: C. camphoraTACCCCGCCTGGGGCGACAC SEQ ID TE forward NO: 68 C. camphoraCTTGCTCAGGCGGCGGGTGC SEQ ID TE reverse NO: 69 cd189 forwardCCGGATCTCGGCCAGGGCTA SEQ ID NO: 70 cd189 reverse TCGATGTCGTGCACCGTCGCSEQ ID NO: 71

Lipid profiles from each of the transformants from each time point werealso generated and compared to the RT-PCR results. Based on the ammonialevels, RT-PCR results and changes in C12-C14 fatty acid levels, it wasconcluded that the Amino acid transporter 01 (Aat-01), Amino acidtransporter 04 (Aat-04), and Ammonium transporter 02 (Amt-02) sequencesdo contain a functional nitrogen-regulatable promoter/5′UTR.

From the RT-PCR results, Aat-01 demonstrated the ability to drive steadystate C. camphora thioesterase mRNA levels up to four times higher thancontrol (C. reinhardtii beta tubulin promoter). The mRNA levels alsocorrelated with nitrogen limitation and a marked increase in C12-C14fatty acid levels. These results demonstrate that the 5′UTR associatedwith the Aat-01 promoter is likely more efficient at driving proteinsynthesis under lipid biosynthesis than the control C. reinhardtiipromoter. Like the Aat-01 promoter, the Aat-04 promoter was able todrive mRNA accumulation up to five times higher than that of the C.reinhardtii control promoter. However, the Aat-04 promoter constructonly produced a modest ability to impact C12-C14 fatty acid levels.These data demonstrate that the Aat-04 promoter is clearly regulatableby nitrogen depletion, but the UTR associated with the promoter likelyfunctions poorly as a translational enhancer. Finally, the Amt-02promoter was similar to the Aat-01 promoter, in that it was able todrive mRNA accumulation up to three times higher than that of thecontrol promoter. The mRNA levels also correlated with nitrogenlimitation and a marked increase in C12-C14 fatty acid levels. Takentogether, all three of these promoters were demonstrated to benitrogen-regulated.

B. Further Characterization of the Ammonium Transporter 3 (Amt03)Promoter and Expression of Various Thioesterases.

As described above, partial cDNAs termed ammonium transporter 02 and 03(amt02 and amt03) were identified. Along with these two partial cDNAs, athird partial cDNA termed ammonium transporter 01 (amt01) was alsoidentified. Alignment of the partial cDNA and the putative translatedamino acid sequences were compared. Results show amt01 to be moredistantly related of the three sequences, while amt02 and amt03 differby only a single amino acid.

Promoters/5′UTRs were generated initially in silico by blasting thepartial cDNA sequences against Roche 454 genomic DNA assemblies andIllumina transcriptome assemblies as described above. Transcript contigsshowing identity to the cDNA encoding amt01, amt02, and amt03 wereidentified, however, the transcript contigs could not differentiatebetween the three mRNAs as the contigs contained sequences shared by allthree. Roche 454 genomic DNA assemblies gave hits to amt02 and amt03cDNA sequences and contained N-terminal protein sequences. PCR wascarried out to clone the 5′ flanking regions. The PCR primers used tovalidate the clone amt02 and amt03 promoter/UTR were:

Amt03 forward: (SEQ ID NO: 85) 5′-GGAGGAATTCGGCCGACAGGACGCGCGTCA-3′Amt03 reverse: (SEQ ID NO: 86) 5′-GGAGACTAGTGGCTGCGACCGGCCTGTG-3′Amt02 forward: (SEQ ID NO: 87) 5′-GGAGGAATTCTCACCAGCGGACAAAGCACCG-3′Amt02 reverse: (SEQ ID NO: 88) 5′-GGAGACTAGTGGCTGCGACCGGCCTCTGG-3′In both cases, the 5′ and 3′ primers contained useful restriction sitesfor the anticipated cloning into expression vectors to validate thefunctionality of these promoter/5′UTR regions.

Pair wise alignments between the DNAs cloned through this combined insilico and PCR-based method and the original cDNA encoding amt02 (SEQ IDNO: 61) and amt03 (SEQ ID NO: 60) were performed. Results of thesealignments showed significant differences between the original cDNAs andthe cloned genomic sequences, indicating that ammonium transporterslikely represent a diverse gene family. Additionally, the promoter/5′UTRclone based on the combined method for amt03 was different than theoriginal amt03 sequence, whereas the amt02 sequences were identical.Further experiments to characterize the amt03 promoter/UTR sequence (SEQID NO: 89) was carried out and described below.

The above identified amt03 promoter/UTR sequence (SEQ ID NO: 89) wastested by cloning this putative promoter/UTR sequence to drive theexpression of four different thioesterases. The expression cassettecontained upstream and downstream homologous recombination sequences tothe 6S locus of the genome (SEQ ID NOs: 82 and 84, respectively). Thecassette also contains a S. cerevisiae SUC2 sucrose invertase cDNA toenable the selection for positive clones on sucrose containing medium.The sucrose invertase expression was driven by the C. reinhardtii betatubulin promoter and also contained a C. vulgaris nitrate reductase3′UTR. The amt03 promoter/UTR sequence was then cloned downstream of thesucrose invertase cassette followed by in-frame thioesterase cDNAsequence from one of four thioesterase genes: (1) C14 thioesterase fromC. camphora; (2) C12 thioesterase from U. californica; (3) C10-C16thioesterase from U. americana; or (4) C10 thioesterase from C.hookeriana and also contained a C. vulgaris nitrate reductase 3′UTR. TheC14 C. camphora thioesterase, C12 U. californica thioesterase, and theC10-C16 U. americana all contained the transit peptide from a Chlorellaprotothecoides stearoyl ACP desaturase. The C10 C. hookerianathioesterase contained the transit peptide from a Prototheca moriformisdelta 12 fatty acid desaturase (FAD). In all cases, the sequences werecodon optimized for expression in Prototheca moriformis. The sequencesto the foregoing thioesterase constructs are described in the SequenceListing:

amt03 promoter/UTR::C. camphora thioesterase construct SEQ ID NO: 90C. camphora thioesterase construct SEQ ID NO: 91U. californica thioesterase construct SEQ ID NO: 92U. americana thioesterase construct SEQ ID NO: 93C. hookeriana thioesterase construct SEQ ID NO: 94

Transgenic lines were generated via biolistic transformation methods asdescribed above in Example 2 into wild type Prototheca moriformis cellsand selection was carried out on sucrose containing plates/medium.Positive lines were then screened for the degree to which their fattyacid profiles were altered. Four lines, one resulting from thetransformation with each of the four above-described constructs, werethen subjected to additional analysis. Line 76 expressed the C. camphoraC14 thioesterase, line 37 expressed the U. californica C12 thioesterase,line 60 expressed the U. americana C10-C16 thioesterase, and line 56expressed the C. hookeriana C10 thioesterase. Each line was grown for 48hours in medium containing sucrose as the sole carbon source and samplesof cells were removed at 14, 24, 36 and 48 hours (seed culture) fordetermination of fatty acid profile via direct transesterification tofatty acid methyl esters and subsequent analysis by GC-FID (describedabove) and for isolation of total RNA. At the end of 48 hours, thesecells were used to inoculate cultures with no or low levels of nitrogen(containing sucrose as the sole carbon source) maintained at either pH5.0 (citrate buffered, 0.05M final concentration) or pH 7.0 (HEPESbuffered, 0.1M final concentration). Culture samples were removed at 12,24, 72 and 108 hours (lipid production) for fatty acid profiling andisolation of total RNA. Ammonia assays of these cultures revealed thatammonia levels fell below the limits of detection (ca. 100 μM) after 24hours in low nitrogen medium.

Real-time RT-PCR assays on the mRNA levels of the thioesterases wereperformed on total RNA from each of the time points collected above andall mRNA levels were normalized to the levels of an internal control RNA(cd189). Primer sets used in real-time PCR are shown in Table 31 below:

TABLE 31 Primer sets for real-time PCR. Gene specific toPrimer sequence 5′-3′ SEQ ID NO: C. camphora TE forwardTACCCCGCCTGGGGCGACAC SEQ ID NO: 68 C. camphora TE reverseCTTGCTCAGGCGGCGGGTGC SEQ ID NO: 69 U. californica TE forwardCTGGGCGACGGCTTCGGCAC SEQ ID NO: 95 U. californica TE reverseAAGTCGCGGCGCATGCCGTT SEQ ID NO: 96 U. americana TE forwardCCCAGCTGCTCACCTGCACC SEQ ID NO: 97 U. americana TE reverseCACCCAAGGCCAACGGCAGCGCCGTG SEQ ID NO: 98 C. hookeriana TE forwardTACCCCGCCTGGGGCGACAC SEQ ID NO: 99 C. hookeriana TE reverseAGCTTGGACAGGCGGCGGGT SEQ ID NO: 100 cd189 reverse TCGATGTCGTGCACCGTCGCSEQ ID NO: 71 cd189 forward CCGGATCTCGGCCAGGGCTA SEQ ID NO: 70

The results from the fatty acid profiles at each of the time points inthe seed culture phase showed very little impact from the thioesterases.With the commencement of the lipid production phase, the fatty acidprofiles were significantly impacted, with the increases that are farmore dramatic for the cultures maintained at pH 7.0 as compared to thecultures at pH 5.0. While the magnitude of the difference between pH 7.0and 5.0 target fatty acid accumulation varied with each thioesterasetested, the overall effect was the same: that the cells grown at pH 5.0showed significantly lower levels of the target fatty acids accumulated,but more than compared to control wild type cells.

Analysis of the RNA isolated from these same samples correlated verywill with the fatty acid profile data, in that there was a clear impactof culture pH on the steady state mRNA levels for each of thethioesterases. Taking the fatty acid accumulation data and the mRNA datatogether, the pH regulation of thioesterase gene expression driven bythe amt03 promoter/UTR was clearly mediated either at the level oftranscription, mRNA stability or both. Additionally, it was observedthat the steady state levels of U. californica mRNA were four logs loweras compared to the steady state levels of C. hookeriana mRNA. Thisobservation is consistent with the hypothesis that the individual mRNAsequences may play a role in controlling expression. These data implythat ammonium uptake in Prototheca moriformis by the amt03 family oftransporters is coupled directly to pH.

Additional fatty acid profile analysis was performed on twelve linesgenerated from the transformation of Prototheca moriformis cells withthe construct amt03 promoter/UTR driving the expression of the U.americana C10-C16 thioesterase. Line 60, described above, was a part ofthe following analysis. Table 32 below shows the lipid profiles of threeof the twelve lines that were analyzed along with the wild type control.

TABLE 32 Fatty acid profiles of transformants containing the U.americana TE driven by the amt03 promoter/UTR. Total Area % C8:0 C10:0C12:0 C14:0 C16:0 C18:0 C18:1 C18:2 Saturates wild type 0.00 0.01 0.041.27 27.20 3.85 58.70 7.18 32.36 Line 40 2.38 20.61 3.41 28.41 29.921.91 8.57 3.74 86.64 Line 44 1.50 20.16 4.44 31.88 26.66 1.88 6.95 5.4286.50 Line 60 0.98 14.56 3.15 27.49 31.76 2.14 12.23 6.36 80.06

As shown in the table above, the levels of total saturates was increaseddramatically over that of wild type with over 2.6 fold in the case ofline 40 compared to wildtype (total saturates from the twelve linesanalyzed ranged from about 63% to over 86%). Additionally, the U.americana thioesterase, when expressed at these levels, dramaticallyreduces the level of unsaturates, especially C18:1 and C18:2 (see lines40 and 44), where in line 44, C18:1 levels are reduced by over 8 foldcompared to the wild type. Also, the U. americana thioesterase (drivenby the amt03 promoter) greatly increases the levels of mid-chain fattyacids. Line 44 shows C10:0-C14:0 levels at greater than 56%,approximately 42 fold higher than the levels seen in the wildtype strainand C8:0-C14:0 levels at greater than 57%. Additional strainstransformed with a construct of the Amt03 promoter driving theexpression of the U. americana thioesterase had representative lipidprofile of: 0.23% C8:0; 9.64% C10:0; 2.62% C12:0; 31.52% C14:0; 37.63%C16:0; 5.34% C18:0; 7.05% C18:1; and 5.03% C18:2, with a total saturatespercentage at 86.98%.

Additional lipid profiles generated from the transformation ofPrototheca moriformis cells with the construct amt03 promoter/UTR (SEQID NO: 89) driving the expression of the C. hookeriana C10 thioesterase(SEQ ID NO: 94). Positive clones expressing this construct were selectedand grown at pH 7.0 conditions. Representative lipid profile from apositive clone was: 9.87% C8:0; 23.97% C10:0; 0.46% C12:0; 1.24% C14:0;10.24% C16:0; 2.45% C18:0; 42.81% C18:1; and 7.32% C18:2. This clone hada C8-C10 percentage of 33.84

Taken together, the data suggest that the amt03 promoter/UTR, and otherpromoters like it, can be used as a tightly regulated promoter, whichmay be particularly useful for expressing a potentially toxic compoundand strict enforcement of gene expression is required. The ability ofPrototheca moriformis to grow under a wide range (at least pH 5.0 to7.0) of pH regimes makes this organism particularly useful incombination with regulatory elements such as the amt03 promoter/UTR.Additionally, the lipid profile data above demonstrates the impressiveability of the amt03 promoter/UTR to drive gene expression.

Example 6: Altering the Levels of Saturated Fatty Acids in theMicroalgae Prototheca moriformis

A. Decreasing Stearoyl ACP Desaturase and Delta 12 Fatty Acid DesaturaseExpression by Gene Knock-Out Approach

As part of a genomics screen using a bioinformatics based approach basedon cDNAs, Illumia transcriptome and Roche 454 sequencing of genomic DNAfrom Prototheca moriformis (UTEX 1435), two specific groups of genesinvolved in fatty acid desaturation were identified: stearoyl ACPdesaturases (SAD) and delta 12 fatty acid desaturases (A12 FAD).Stearoyl ACP desaturase enzymes are part of the lipid synthesis pathwayand they function to introduce double bonds into the fatty acyl chains,for example, the synthesis of C18:1 fatty acids from C18:0 fatty acids.Delta 12 fatty acid desaturases are also part of the lipid synthesispathway and they function to introduce double bonds into alreadyunsaturated fatty acids, for example, the synthesis of C18:2 fatty acidsfrom C18:1 fatty acids. Southern blot analysis using probes based on thetwo classes of fatty acid desaturase genes identified during thebioinformatics efforts indicated that each class of desaturase genes waslikely comprised of multiple family members. Additionally the genesencoding stearoyl ACP desaturases fell into two distinct families. Basedon these results, three gene disruption constructs were designed topotentially disrupt multiple gene family members by targeting morehighly conserved coding regions within each family of desaturaseenzymes.

Three homologous recombination targeting constructs were designed using:(1) highly conserved portions of the coding sequence of delta 12 fattyacid desaturase (d12FAD) family members and (2) two constructs targetingeach of the two distinct families of SAD, each with conserved regions ofthe coding sequences from each family. This strategy would embed aselectable marker gene (the suc2 sucrose invertase cassette from S.cerevisiae conferring the ability to hydrolyze sucrose) into thesehighly conserved coding regions (targeting multiple family members)rather than a classic gene replacement strategy where the homologousrecombination would target flanking regions of the targeted gene.

All constructs were introduced into the cells by biolistictransformation using the methods described above and constructs werelinearized before being shot into the cells. Transformants were selectedon sucrose containing plates/media and changes in lipid profile wereassayed using the above-described method. Relevant sequences from eachof the three targeting constructs are listed below.

Description SEQ ID NO: 5′ sequence from coding region of d12FAD from SEQID NO: 72 targeting construct 3′ sequence from coding region of d12FADfrom SEQ ID NO: 73 targeting construct d12FAD targeting construct cDNAsequence SEQ ID NO: 74 5′ sequence from coding region of SAD2A SEQ IDNO: 75 3′ sequence from coding region of SAD2A SEQ ID NO: 76 SAD2Atargeting construct cDNA sequence SEQ ID NO: 77 5′ sequence from codingregion os SAD2B SEQ ID NO: 78 3′ sequence from coding region of SAD2BSEQ ID NO: 79 SAD2B targeting construct cDNA sequence SEQ ID NO: 80

Representative positive clones from transformations with each of theconstructs were picked and the lipid profiles for these clones weredetermined (expressed in Area %) and summarized in Table 33 below.

TABLE 33 Lipid profiles for desaturase knockouts. Fatty Acid d12FAD KOSAD2A KO SAD2B KO wt UTEX 1435 C8:0 0 0 0 0 C10:0 0.01 0.01 0.01 0.01C12:0 0.03 0.03 0.03 0.03 C14:0 1.08 0.985 0.795 1.46 C16:0 24.42 25.33523.66 29.87 C18:0 6.85 12.89 19.555 3.345 C18:1 58.35 47.865 43.11554.09 C18:2 7.33 10.27 9.83 9.1 C18:3 alpha 0.83 0.86 1 0.89 C20:0 0.480.86 1.175 0.325

Each of the construct had a measurable impact on the desired class offatty acid and in all three cases C18:0 levels increased markedly,particularly with the two SAD knockouts. Further comparison of multipleclones from the SAD knockouts indicated that the SAD2B knockout lineshad significantly greater reductions in C18:1 fatty acids than the C18:1fatty acid levels observed with the SAD2A knockout lines.

Additional Δ12 fatty acid desaturase (FAD) knockouts were generated in aPrototheca moriformis background using the methods described above. Inorder to identify potential homologous of Δ12FADs, the following primerswere used in order to amplify a genomic region encoding a putative FAD:

Primer 1 SEQ ID NO: 101 5′-TCACTTCATGCCGGCGGTCC-3′ Primer 2SEQ ID NO: 102 5′-GCGCTCCTGCTTGGCTCGAA-3′The sequences resulting from the genomic amplification of Protothecamoriformis genomic DNA using the above primers were highly similar, butindicated that multiple genes or alleles of Δ12FADs exist in Prototheca.

Based on this result, two gene disruption constructs were designed thatsought to inactivate one or more Δ12FAD genes. The strategy would toembed a sucrose invertase (suc2 from S. cerevisiae) cassette, thusconferring the ability to hydrolyze sucrose as a selectable marker, intohighly conserved coding regions rather than use a classic genereplacement strategy. The first construct, termed pSZ1124, contained 5′and 3′ genomic targeting sequences flanking a C. reinhardtii β-tubulinpromoter driving the expression of the S. cerevisiae suc2 gene and aChlorella vulgaris nitrate reductase 3′UTR (S. cerevisiae suc2cassette). The second construct, termed pSZ1125, contained 5′ and 3′genomic targeting sequences flanking a C. reinhardtii β-tubulin promoterdriving the expression of the S. cerevisiae suc2 gene and a Chlorellavulgaris nitrate reductase 3′UTR. The relevant sequences of theconstructs are listed in the Sequence Listing:

pSZ1124 (FAD2B) 5′ genomic targeting sequence SEQ ID NO: 103pSZ1124 (FAD2B) 3′ genomic targeting sequence SEQ ID NO: 104S. cerevisiae suc2 cassette SEQ ID NO: 105pSZ1125 (FAD2C) 5′ genomic targeting sequence SEQ ID NO: 106pSZ1125 (FAD2C) 3′ genomic targeting sequence SEQ ID NO: 107

pSZ1124 and pSZ1125 were each introduced into a Prototheca moriformisbackground and positive clones were selected based on the ability tohydrolyze sucrose. Table 34 summarizes the lipid profiles (in Area %,generated using methods described above) obtained in two transgeniclines in which pSZ1124 and pSZ1125 targeting vectors were utilized.

TABLE 34 Lipid profiles of Δ12 FAD knockouts C10:0 C12:0 C14:0 C16:0C16:1 C18:0 C18:1 C18:2 C18:3α parent 0.01 0.03 1.15 26.13 1.32 4.3957.20 8.13 0.61 FAD2B 0.02 0.03 0.80 12.84 1.92 0.86 74.74 7.08 0.33FAD2C 0.02 0.04 1.42 25.85 1.65 2.44 66.11 1.39 0.22

The transgenic containing the FAD2B (pSZ1124) construct gave a veryinteresting and unexpected result in lipid profile, in that the C18:2levels, which would be expected to decrease, only decreased by about onearea %. However, the C18:1 fatty acid levels increased significantly,almost exclusively at the expense of the C16:0 levels, which decreasedsignificantly. The transgenic containing the FAD2C (pSZ1125) constructalso gave a change in lipid profile: the levels of C18:2 are reducedsignificantly along with a corresponding increase in C18:1 levels.

Beef Tallow Mimetic

One positive clone generated from the above SAD2B knockout experiment asdescribed above was selected to be used as the background for thefurther introduction of a C14-preferring fatty acyl-ACP thioesterasegene. The construct introducing the C. camphora C14-preferringthioesterase contained targeting sequence to the 6S genomic region(allowing for targeted integration of the transforming DNA viahomologous recombination) and the expression construct contained the C.reinhardtii β-tubulin promoter driving the expression of the neoR genewith the Chlorella vulgaris nitrate reductase 3′UTR, followed by asecond C. reinhardtii β-tubulin promoter driving the expression of acodon-optimized C. camphora thioesterase with a Chlorella protothecoidesstearoyl ACP desaturase transit peptide with a second Chlorella vulgarisnitrate reductase 3′UTR. The 5′ 6S genomic donor sequence is listed inSEQ ID NO: 82; the 3′ 6S genomic donor sequence is listed in SEQ ID NO:84; and the relevant expression construct for the C. camphorathioesterase is listed in SEQ ID NO: 83.

Transformation was carried out using biolistic methods as describedabove and the cells were allowed to recover for 24 hours on platescontaining 2% sucrose. After this time, the cells were re-suspended andre-plated on plates containing 2% sucrose and 50 μg/ml G418 forselection. Nine clones out of the positive clones generated wereselected for lipid production and lipid profile. The nine transgenicclones (with the SAD2B KO and expressing C. camphora C14-preferringthioesterase) were cultured as described above and analyzed for lipidprofile. The results are summarized below in Table 35. The lipid profilefor tallow is also included in Table 35 below (National Research Council1976: Fat Content and Composition of Animal Product).

TABLE 35 Lipid profile of thioesterase transformed clones. C10:0 C12:0C14:0 C16:0 C16:1 C18:0 C18:1 C18:2 C18:3 C20 SAD2BKO 0.01 0.33 6.1324.24 0.19 11.08 42.03 13.45 0.98 0.73 C. camphora TE clone 1 SAD2BKO0.01 0.16 3.42 23.80 0.40 9.40 50.62 10.2 0.62 0.70 C. camphora TE clone2 SAD2BKO 0.01 0.20 4.21 25.69 0.40 7.79 50.51 9.37 0.66 0.63 C.camphora TE clone 3 SAD2BKO 0.01 0.21 4.29 23.57 0.31 9.44 50.07 10.070.70 0.70 C. camphora TE clone 4 SAD2BKO 0.01 0.18 3.87 24.42 0.32 9.2449.75 10.17 0.71 0.71 C. camphora TE clone 5 SAD2BKO 0.01 0.28 5.3423.78 0.33 9.12 49.12 10.00 0.68 0.70 C. camphora TE clone 6 SAD2BKO0.01 0.15 3.09 23.07 0.32 10.08 51.21 10.00 0.66 0.74 C. camphora TEclone 7 SAD2BKO 0.01 0.29 5.33 24.62 0.37 7.02 49.67 10.74 0.69 0.70 C.camphora TE clone 8 SAD2BKO 0.01 0.12 2.74 25.13 0.30 10.17 50.18 9.420.71 0.71 C. camphora TE clone 9 wt UTEX 0.01 0.02 0.96 23.06 0.79 3.1461.82 9.06 0.46 0.27 1435 SAD2BKO 0.01 0.03 0.80 23.66 0.13 19.56 43.129.83 1.00 1.18 Tallow 0.00 0.00 4.00 26.00 3.00 14.00 41.00 3.00 1.000.00

As can be seen in Table 35, the lipid profiles of the transgenic linesare quite similar to the lipid profile of tallow. Taken collectively,the data demonstrate the utility of combining specific transgenicbackgrounds, in this case, a SAD2B knockout with a C14-preferringthioesterase (from C. camphora), to generate an transgenic algal strainthat produce oil similar to the lipid profile of tallow.

B. RNAi Approach to Down-Regulation of Delta 12 Desaturase Gene (FADc)in Prototheca Cells

Vectors down-regulating FADc (delta 12 desaturase gene) gene expressionby RNAi were introduced into a Prototheca moriformis UTEX 1435 geneticbackground. The Saccharomyces cerevisiae suc2 sucrose invertase gene wasutilized as a selectable marker, conferring the ability to grow onsucrose as a sole-carbon source to positive clones. The first type ofconstructs utilized a portion of the first exon of the FADc codingregion linked in cis to its first intron followed by a repeat unit ofthe first exon in reverse orientation. This type of constructstheoretically leads to the formation of a hairpin RNA when expressed asmRNA. Two constructs of this first type were created, one driven by thePrototheca moriformis Amt03 promoter (SEQ ID NO: 89), termed pSZ1468,and a second construct driven by the Chlamydomomas reinhardtii β-tubulinpromoter (SEQ ID NO: 114), termed pSZ 1469. A second type of constructsutilized the large FADc exon 2 in the antisense orientation driven byeither the Prototheca moriformis Amt03 promoter (SEQ ID NO: 89), termedpSZ1470, or driven by the Chlamydomomas reinhardtii β-tubulin promoter(SEQ ID NO: 114), termed pSZ1471. All four constructs had a S.cerevisiae suc2 sucrose invertase cassette (SEQ ID NO: 159) and a 5′(SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologous recombinationtargeting sequences (flanking the construct) to the 6S genomic regionfor integration into the nuclear genome. Sequences of the FADc portionsof each RNAi construct along with the relevant portions of eachconstruct are listed in the Sequence Listing as:

Description SEQ ID NO: pSZ1468 FADc RNAi hairpin cassette SEQ ID NO: 163Relevant portions of the pSZ1468 construct SEQ ID NO: 164 pSZ1469 FADcRNAi hairpin cassette SEQ ID NO: 165 Relevant portions of the pSZ1469construct SEQ ID NO: 166 pSZ1470 FADc exon 2 RNAi cassette SEQ ID NO:167 Relevant portions of the pSZ1470 construct SEQ ID NO: 168 pSZ1471FADc exon 2 RNAi cassette SEQ ID NO: 169 Relevant portions of thepSZ1471 construct SEQ ID NO: 170

Each of the four constructs were transformed into a Protothecamoriformis background and positive clones were screened using plateswith sucrose as the sole carbon source. Positive clones were picked fromeach transformation and a subset were selected to determine the impactof the hairpin and antisense cassettes contained in pSZ1468, pSZ1469,pSZ1470 and pSZ1471 on fatty acid profiles. The selected clones fromeach transformation were grown under lipid producing conditions and thelipid profiles were determined using direct transesterification methodsas described above. Representative lipid profiles from each of thetransformations are summarized below in Table 36. Wildtype 1 and 2 cellswere untransformed Prototheca moriformis cells that were run with eachof the transformants as a negative control.

TABLE 36 Lipid profiles of Prototheca moriformis cells containing RNAiconstructs to down-regulate the expression of delta 12 desaturase gene(FADc). Strain C10:0 C12:0 C14:0 C16:0 C18:0 C18:1 C18:2 wildtype 1 0.010.03 1.20 27.08 4.01 57.58 7.81 pSZ1468 0.01 0.04 1.33 25.95 3.68 65.601.25 clone A pSZ1468 0.01 0.03 1.18 23.43 2.84 65.32 4.91 clone BpSZ1468 0.01 0.04 1.34 23.18 4.27 63.65 5.17 clone C pSZ1468 0.01 0.031.24 23.00 3.85 61.92 7.62 clone D pSZ1470 0.01 0.03 1.23 24.79 4.3358.43 8.92 clone A pSZ1470 0.01 0.03 1.26 24.91 4.14 57.59 9.64 clone BpSZ1470 0.01 0.03 1.21 23.35 4.75 58.52 9.70 clone C wildtype 2 0.010.03 0.98 24.65 3.68 62.48 6.26 pSZ1469 0.01 0.03 1.05 21.74 2.71 71.331.22 clone A pSZ1469 0.01 0.03 1.01 22.60 2.98 70.19 1.27 clone BpSZ1469 0.01 0.03 1.03 19.82 2.38 72.95 1.82 clone C pSZ1469 0.01 0.031.03 20.54 2.66 70.96 2.71 clone D pSZ1471 0.01 0.03 1.03 18.42 2.6366.94 8.55 clone A pSZ1471 0.01 0.03 0.94 18.61 2.58 67.13 8.66 clone BpSZ1471 0.01 0.03 1.00 18.31 2.46 67.41 8.71 clone C pSZ1471 0.01 0.030.93 18.82 2.54 66.84 8.77 clone D

The above summarized results showed that the hairpin constructs, pSZ1468and pSZ1469, showed specific expected phenotypes, namely a reduction inC18:2 fatty acid levels and an increase in C18:1 fatty acid levels ascompared to wildtype1 and wildtype 2, respectively. The antisenseconstructs, pSZ1470 and pSZ1471 did not result a decrease in C18:2 fattyacid levels, but instead showed a slight increase when compared towildtype 1 and wildtype 2, respectively and a slight decrease in C16:0fatty acid levels.

C. Expression of an Exogenous Stearoyl-ACP Desaturase

The Olea europaea stearoyl-ACP desaturase (GenBank Accession No.AAB67840.1) was introduced into a Prototheca moriformis UTEX1435 geneticbackground. The expression construct contained a 5′ (SEQ ID NO: 82) and3′ (SEQ ID NO: 84) homologous recombination targeting sequences(flanking the construct) to the 6S genomic region for integration intothe nuclear genome and a S. cerevisiae suc2 sucrose invertase codingregion under the control of C. reinhardtii β-tubulin promoter/5′UTR andChlorella vulgaris nitrate reductase 3′ UTR. This S. cerevisiae suc2expression cassette is listed as SEQ ID NO: 159 and served as aselection marker. The Olea europaea stearoyl-ACP desaturase codingregion was under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR,and the native transit peptide was replaced with the Chlorellaprotothecoides stearoyl-ACP desaturase transit peptide (SEQ ID NO: 49.The codon-optimized cDNA sequences and amino acid sequences (with thereplaced transit peptide) are listed in the Sequence Listing as SEQ IDNO: 171 and SEQ ID NO: 172, respectively. The entire O. europaea SADexpression cassette was termed pSZ1377 and transformed into a Protothecamoriformis genetic background. Positive clones were screened on plateswith sucrose as the sole carbon source. A subset of the positive cloneswere selected and grown under lipid production conditions and lipidprofiles were determined using direct transesterification methods asdescribed above. The lipid profiles of the selected clones aresummarized in Table 37 below.

TABLE 37 Lipid profiles of Olea europaea stearoyl-ACP desaturasetransgenic Prototheca moriformis cells. Strain C14:0 C16:0 C18:0 C18:1C18:2 wildtype 0.88 22.82 3.78 64.43 6.54 pSZ1377 0.94 18.60 1.50 69.457.67 clone A pSZ1377 0.93 18.98 1.35 69.12 7.67 clone B pSZ1377 0.9319.01 2.31 68.56 7.43 clone C

The above summarized results demonstrate that the introduction of anheterologous desaturase, in this case a stearoyl-ACP desaturase fromOlea europaea, can result in higher levels of C18:1 fatty acid and aconcomitant decrease in C18:0 and C16:0 fatty acid levels.

Example 7: Engineering Prototheca to Produce Hydroxylated Fatty Acids

The Ricinus communis oleate 12-hydroxylase (Rc12hydro) (GenBankAccession No. AAC49010.1) was introduced into a Prototheca moriformisUTEX1435 genetic background. The expression construct contained a 5′(SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologous recombinationtargeting sequences (flanking the construct) to the 6S genomic regionfor integration into the nuclear genome and a S. cerevisiae suc2 sucroseinvertase coding region under the control of C. reinhardtii β-tubulinpromoter/5′UTR and Chlorella vulgaris nitrate reductase 3′ UTR. This S.cerevisiae suc2 expression cassette is listed as SEQ ID NO: 159 andserved as a selection marker. The Ricinus communis oleate 12-hydroxylasecoding region was under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR.The codon-optimized cDNA sequences and amino acid sequences are listedin the Sequence Listing as SEQ ID NO: 173 and SEQ ID NO: 174,respectively. The entire Rc12hydro expression cassette was termedpSZ1419 and transformed into a Prototheca moriformis genetic background.Positive clones were screened on plates with sucrose as the sole carbonsource. A subset of the positive clones were selected and grown underlipid production conditions and screened for the product of the R.communis oleate 12-hydroxylase, namely, ricinoleic acid using a GC/MSmethod.

The GC/MS method used to detect any ricinoleic acid produced in positiveRc12hydro transgenics was as follows. Samples of positive clones and awildtype control were dried and then suspended in 2.2 mL of 4.5 H₂SO₄ inmethanol-toluene, 10:1 (v/v). The mixture was then heated at 70-75° C.for 3.5 hours with intermittent sonication and vortexing. After coolingto room temperature, 2 mL of 6% K₂CO₃ (aq) and 2 mL of heptane wasadded, the mixture was then vortexed vigorously and the separation oflayers was hastened by centrifugation at 900 rpm for 2 minutes. Theupper layer was removed and concentrated to dryness with a stream ofnitrogen. To the resulting oil was added 500 μL of dry pyridine and 500μL of BSTFA/1% TMCS (Thermo Scientific). The resulting solution washeated at 70-75° C. for 1.5 hours and then concentrated to dryness witha stream of nitrogen. The residue was then resuspended in 2 mL ofheptane and reconcentrated. Samples were resuspended in 2 mL of heptaneand analyzed by GC/MS on a Thermo Trace GC Ultra/DSQII system in EI modeusing selective ion monitoring of the base-peak of the TMS either ofmethyl ricinoleate (m/z 187). Fatty acid methyl esters were separated ona Restek Rxi-5Sil MS column (0.25 mm ID, 30 m length, 0.5 μm filmthickness) using helium as the carrier gas at a flow of 1 mL/min. Theinitial temperature of the column was held at 130° C. for 4 minutes,followed by a ramp of 4° C./min to a final temperature of 240° C. Thepresence of ricinoleic acid in samples was confirmed by comparison ofretention time and full-scan mass spectra to an authentic sample ofricinoleic acid treated as described above. FIG. 2 shows the GCretention time of a representative positive transgenic clone compared tothe ricinoleic acid standard and a wildtype control. The positivetransgenic clone has a derivable peak at RT:33.22/33.23 whichcorresponds to a similar peak in the ricinoleic acid standard,indicating the presence of derivable ricinoleic acid in both thetransgenic clone and the positive control. This peak was entirelylacking in the wildtype control sample.

Example 8: Engineering Prototheca with Alternative Selectable Markers

A. Expression of a Secretable α-Galactosidase in Prototheca moriformis

Methods and effects of expressing a heterologous sucrose invertase genein Prototheca species have been previously described in PCT ApplicationNo. PCT/US2009/66142, hereby incorporated by reference. The expressionof other heterologous polysaccharide degrading enzymes was examined inthis Example. The ability to grow on melibiose (α-D-gal-glu) byPrototheca moriformis UTEX 1435 with one of the following exogenous geneencoding a α-galactosidase was tested: MEL1 gene from Saccharomycescarlbergensis (amino acid sequence corresponding to NCBI accessionnumber P04824), AglC gene from Aspergillus niger (amino acid sequencecorresponding to NCBI accession number Q9UUZ4), and the α-galactosidasefrom the higher plant Cyamopsis tetragobobola (Guar bean) (amino acidsequence corresponding to NCBI accession number P14749). The aboveaccession numbers and corresponding amino acid sequences are herebyincorporated by reference. In all cases, genes were optimized accordingto the preferred codon usage in Prototheca moriformis. The relevantportions of the expression cassette are listed below along with theSequence Listing numbers. All expression cassettes used the 5′ and 3′C1p homologous recombination targeting sequences for stable genomicintegration, the Chlamydomonas reinhardtii TUB2 promoter/5′UTR, and theChlorella vulgaris nitrate reductase 3′UTR.

S. carlbergensis MEL1 amino acid sequence SEQ ID NO: 108

S. carlbergensis MEL1 amino acid sequence signal peptide SEQ ID NO: 109

S. carlbergensis MEL1 transformation cassette SEQ ID NO: 110

S. carlbergensis MEL1 sequence (codon optimized) SEQ ID NO: 111

5′ C1p homologous recombination targeting sequence SEQ ID NO: 112

3′ C1p homologous recombination targeting sequence SEQ ID NO: 113

Chlamydomonas reinhardtii TUB2 promoter/5′UTR SEQ ID NO: 114

Chlorella vulgaris nitrate reductase 3′UTR SEQ ID NO: 115

A. niger AlgC amino acid sequence SEQ ID NO: 116

A. niger AlgC amino acid sequence signal peptide SEQ ID NO: 117

A. niger AlgC sequence (codon optimized) SEQ ID NO: 118

A. niger AlgC transformation cassette SEQ ID NO: 119

C. tetragonobola α-galactosidase amino acid sequence SEQ ID NO: 120

C. tetragonobola α-galactosidase sequence (codon optimized) SEQ ID NO:121

C. tetragonobola α-galactosidase transformation cassette SEQ ID NO: 122

Prototheca moriformis cells were transformed with each of the threeexpression cassettes containing S. carlbergensis MEL1, A. niger AlgC, orC. tetragonobola α-galactosidase gene using the biolistic transformationmethods as described in Example 2 above. Positive clones were screenedusing plates containing 2% melibiose as the sole carbon source. Nocolonies appeared on the plates for the C. tetragonobola expressioncassette transformants. Positive clones were picked from the platescontaining the S. carlbergensis MEL1 transformants and the A. niger AlgCtransformants. Integration of the transforming DNA was confirmed usingPCR with primers targeting a portion of the C. vulgaris 3′UTR and the 3′C1p homologous recombination targeting sequence.

5′ primer C.vulgaris 3′UTR:downstream C1p sequence (SEQ ID NO: 123)ACTGCAATGCTGATGCACGGGA 3′primer C.vulgaris 3′UTR:downstream C1p sequence (SEQ ID NO: 124)TCCAGGTCCTTTTCGCACT

As a negative control, genomic DNA from untransformed Protothecamoriformis cells were also amplified with the primer set. No productswere amplified from genomic DNA from the wild type cells.

Several positive clones from each of the S. carlbergensis MEL1transformants and the A. niger AlgC transformants (as confirmed by PCR)were tested for their ability to grow on melibiose as the sole carbonsource in liquid media. These selected clones were grown for 3 days inconditions and base medium described in Example 1 above with melibioseas the sole carbon source. All clones containing eitherα-galactosidase-encoding genes grew robustly during this time, while theuntransformed wild type strain and Prototheca moriformis expressing aSaccharomyces cerevisiae SUC2 sucrose invertase both grew poorly on themelibiose media. These results suggest that the α-galactosidase encodinggenes may be used as a selectable marker for transformation. Also, thesedata indicate that the native signal peptides present in the S.carlbergensis MEL1 (SEQ ID NO: 109) or A. niger AlgC (SEQ ID NO: 117)are useful for targeting proteins to the periplasm in Protothecamoriformis cells.

B. THIC Genes Complements Thiamine Auxotrophy in Prototheca

Thiamine prototrophy in Prototheca moriformis cells was examined usingexpression of exogenous THIC genes. Thiamine biosynthesis in plants andalgae is typically carried out in the plastid, hence most nuclearencoded proteins involved in its production will need to be efficientlytargeted to the plastid. DNA sequencing and transcriptome sequencing ofPrototheca moriformis cells revealed that all of the genes encoding thethiamine biosynthetic enzymes were present in the genome, with theexception of THIC. To dissect the lesion responsible for thiamineauxotrophy at the biochemical level, the growth of Prototheca moriformiscells under five different regimes were examined: (1) in the presence of2 μM thiamine hydrochloride; (2) without thiamine; (3) without thiamine,but with 2 μM hydroxyethyl thiazole (THZ); (4) without thiamine, butwith 2 μM 2-methyl-4-amino-5-(aminomethyl)pyrimidine (PYR); and (5)without thiamine, but with 2 μM THZ and 2 μM PYR. Results from thegrowth experiments under these 5 different conditions indicated thatPrototheca moriformis cells are capable of de novo synthesis, but canonly produce thiamine pyrophosphate (TPP) if the PYR precursor isprovided. This result is consistent with the hypothesis that thethiamine auxotrophy of Prototheca moriformis is due to the inability tosynthesize hydroxymethylpyrimidine phosphate (HMP-P) from aminoimidazoleribonucleotide, which is the conversion catalyze by THIC enzyme.

Prototheca moriformis cells were transformed using the biolistictransformation methods described above in Example 2, expressing theCoccomyxa C-169 THIC (amino acid sequence corresponding to JGI ProteinID 30481, and hereby incorporated by reference) and a S. cerevisiae SUC2sucrose invertase as the selective marker. This expression constructcontained the native transit peptide sequence from Coccomyxa C-169 THIC,upstream and downstream homologous recombination targeting sequences tothe 6S region of genomic DNA, a C. reinhardtii TUB2 promoter/5′UTRregion (SEQ ID NO: 104), and a Chlorella vulgaris nitrate reductase3′UTR (SEQ ID NO: 115). The S. cerevisiae SUC2 expression was alsodriven by a C. reinhardtii TUB2 promoter/5′UTR region (SEQ ID NO: 114)and contained a Chlorella vulgaris nitrate reductase 3′UTR (SEQ ID NO:115). Genes were optimized according to the preferred codon usage inPrototheca moriformis. The relevant expression cassette sequences arelisted in the Sequence Listing and detailed below:

Coccomyxa C-169 THIC amino acid sequence SEQ ID NO: 125Coccomyxa C-169 THIC amino acid sequence native transit peptide SEQ IDNO: 126Coccomyxa C-169 THIC transformation cassette SEQ ID NO: 127Coccomyxa C-169 THIC sequence (codon optimized) SEQ ID NO: 128S. cerevisiae SUC2 sequence (codon optimized) SEQ ID NO: 1295′ 6S homologous recombination targeting sequence SEQ ID NO: 823′ 6S homologous recombination targeting sequence SEQ ID NO: 84Selection of positive clones were performed on plates without thiamineand containing sucrose as the sole carbon source. Positive clones wereconfirmed using PCR with a 5′ primer that binds within the CoccomyxaC-169 THIC gene and a 3′ primer that anneals downstream of thetransforming DNA in the 6S locus. PCR confirmed positive clones werealso confirmed using Southern blot assays.

To observe the thiamine auxotrophy of wildtype Prototheca moriformiscells, it was necessary to first deplete cells of internal thiaminereserves. To test growth in medium without thiamine, cells were firstgrown to stationary phase in medium containing 2 μM thiamine and thenthe cells were diluted to an optical density at 750 nm (OD750) ofapproximately 0.05 in medium without thiamine. The diluted cells werethen grown once more to stationary phase in medium without thiamine(about 2-3 days). These thiamine-depleted cells were used to inoculatecultures for growth studies in medium without thiamine. Wildtype cellswere grown in medium with glucose as the carbon source (with or withoutthiamine) and positive clones with the native transit peptide CoccomyxaC-169 THIC construct were grown in medium with sucrose as the solecarbon source. Growth was measured by monitoring the absorbance at 750nm. Results of the growth experiments showed substantial greater growthin thiamine-free medium of strains expressing the transgene compared towildtype cells in thiamine-free medium. However, the transformantsfailed to achieve the growth rate and cell densities of wildtype cellsin thiamine-containing media. There was also a strong correlationbetween the amount of growth in the transformant clones in thiamine-freemedium and the copy number of the integrated Coccomyxa enzyme (i.e., themore copy numbers of the transgene, the better the growth of the cellsin thiamine-free medium).

Additional transformants were generated using expression constructscontaining the Coccomyxa THIC, the Arabidopsis thaliana THIC gene, andthe Synechocystis sp. PCC 6803 thiC gene. In the case of the Coccomyxaand the A. thaliana THIC gene, the native transit peptide sequence wasreplaced with the transit peptide sequence from a Chlorellaprotothecoides stearoyl-ACP desaturase (SAD) gene. Synechocystis sp. isa cyanobacterium and the thiC protein does not contain a native transitpeptide sequence. In the Synechocystis sp thiC construct, the transitpeptide sequence from a Chlorella protothecoides SAD gene was fused tothe N-terminus of the Synechocystis sp. thiC. In all cases, thesequences were codon optimized for expression in Prototheca moriformis.All three of the foregoing constructs contained a upstream anddownstream homologous recombination targeting sequence to the 6S regionof the genome (SEQ ID NOs: 82 and 84), a Chlorella protothecoides actinpromoter/5′ UTR, and a Chlorella protothecoides EF1A gene 3′UTR. Allthree constructs contained a neoR gene driven by the C. reinhardtii TUB2promoter/5′UTR (SEQ ID NO: 114) and contained the C. vulgaris 3′UTR (SEQID NO: 115), conferring the selection by G418. The amino acid sequenceof the A. thaliana THIC corresponded to NCBI accession number NP_180524and the amino acid sequence of the Synechocystis sp. thiC correspondedto NCBI accession number NP_442586, both sequences hereby incorporatedby reference. The relevant expression cassette sequences are listed inthe Sequence Listing and detailed below:

-   Coccomyxa THIC expression construct with C. protothecoides transit    peptide SEQ ID NO: 130-   Coccomyxa THIC with C. protothecoides transit peptide SEQ ID NO: 131-   C. protothecoides actin promoter/5′ UTR SEQ ID NO: 132-   C. protothecoides EF1A 3′UTR SEQ ID NO: 133-   A. thaliana THIC expression construct SEQ ID NO: 134-   A. thaliana THIC with C. protothecoides transit peptide SEQ ID NO:    135-   A. thaliana THIC amino acid sequence with native transit peptide SEQ    ID NO: 136-   Synechocystis sp. thiC expression construct SEQ ID NO: 137-   Synechocystis sp. thiC with C. protothecoides transit peptide SEQ ID    NO: 138-   Synechocystis sp. thiC amino acid sequence SEQ ID NO: 139-   neoR gene SEQ ID NO: 140

Positive clones were screened on plates containing G418 and severalclones from each transformation were picked for verification by PCR.Integration of the transforming DNA constructs containing the CoccomyxaC-169 (with C. protothecoides transit peptide), A. thaliana andSynechocystis sp. PCC 6803 THIC genes, respectively into the 6S locus ofthe genome was confirmed using PCR analysis with the following primers:

5′ THIC Coccomyxa confirmation primer sequence (SEQ ID NO: 141)ACGTCGCGACCCATGCTTCC 3′ THIC confirmation primer sequence(SEQ ID NO: 142) GGGTGATCGCCTACAAGA 5′THIC A. thaliana confirmation primer sequence (SEQ ID NO: 143)GCGTCATCGCCTACAAGA 5′ thiC Synechocystis sp. confirmation primersequence (SEQ ID NO: 144) CGATGCTGTGCTACGTGA

Growth experiments on thiamine depleted cells (as described above) wereperformed using selected confirmed positive clones from transformants ofeach of the different constructs in medium containing G418. Alltransformants were able to grow (with varying degrees of robustness) inthiamine-free medium. Comparison of the growth of the transformants inthiamine-free medium to wild type cells on thiamine-containing mediumshowed the following ranking with respect to their ability to supportgrowth in thiamine-free medium: (1) A. thaliana transformants; (2)Coccomyxa C-169 (with C. protothecoides transit peptide) transformants;and (3) Synechocystis sp. transformants. These results suggest thatwhile a single copy of A. thaliana THIC was able to complement thiamineauxotrophy in Prototheca moriformis cells, multiple copies of CoccomyxaC-169 (with either the native transit peptide sequence or a transitpeptide sequence from C. protothecoides) and Synechocystis sp. THIC wasrequired to enable rapid growth in the absence of thiamine. Given thevariability in results of the different THIC from the different sources,the ability of any particular THIC gene to fully complement the lesionpresent in Prototheca species is not predictable.

An alignment of the three THIC amino acid sequences was performed. Whilethere exist significant sequence conservation between thiC fromSynechocystis sp. compared to the THICs from Coccomyxa and A. thaliana(41% identity at the amino acid level), the cyanobacterial protein ismissing a domain at the N-terminus that is well-conserved in the algaland plant proteins. Despite the missing domain (and presumably resultingin structural differences), the construct expressing the Synechocystissp. thiC was able to at least partially restore thiamine prototrophic inPrototheca moriformis cells.

Example 9: Fuel Production

A. Extraction of Oil from Microalgae Using an Expeller Press and a PressAid

Microalgal biomass containing 38% oil by DCW was dried using a drumdryer resulting in resulting moisture content of 5-5.5%. The biomass wasfed into a French L250 press. 30.4 kg (67 lbs.) of biomass was fedthrough the press and no oil was recovered. The same dried microbialbiomass combined with varying percentage of switchgrass as a press aidwas fed through the press. The combination of dried microbial biomassand 20% w/w switchgrass yielded the best overall percentage oilrecovery. The pressed cakes were then subjected to hexane extraction andthe final yield for the 20% switchgrass condition was 61.6% of the totalavailable oil (calculated by weight). Biomass with above 50% oil drycell weight did not require the use of a pressing aid such asswitchgrass in order to liberate oil. Other methods of extraction of oilfrom microalgae using an expeller press are described in PCT ApplicationNo. PCT/US2010/31108 and is hereby incorporated by reference.

B. Production of Biodiesel from Prototheca Oil

Degummed oil from Prototheca moriformis UTEX 1435, produced according tothe methods described above, was subjected to transesterification toproduce fatty acid methyl esters. Results are shown in Table 38 below.

The lipid profile of the oil was:

C10:0 0.02 C12:0 0.06 C14:0 1.81 C14.1 0.07 C16:0 24.53 C16:1 1.22 C18:02.34 C18:1 59.21 C18:2 8.91 C18:3 0.28 C20:0 0.23 C20:1 0.10 C20:1 0.08C21:0 0.02 C22:0 0.06 C24:0 0.10

TABLE 38 Biodiesel profile from Prototheca moriformis triglyceride oil.Method Test Result Units ASTM Cold Soak Filterability of Filtration Time120 sec D6751 A1 Biodiesel Blend Fuels Volume Filtered 300 ml ASTM D93Pensky-Martens Closed Cup Procedure Used A Flash Point Corrected Flash165.0 ° C. Point ASTM Water and Sediment in Middle Sediment and Water0.000 Vol % D2709 Distillate Fuels (Centrifuge Method) EN 14538Determination of Ca and Mg Sum of (Ca and <1 mg/kg Content by ICP OESMg) EN 14538 Determination of Ca and Mg Sum of (Na and K) <1 mg/kgContent by ICP OES ASTM D445 Kinematic/Dynamic Kinematic Viscosity 4.873mm²/s Viscosity @ 104° F/40° C. ASTM D874 Sulfated Ash from LubricatingSulfated Ash <0.005 Wt % Oils and Additives ASTM Determination of TotalSulfur Sulfur, mg/kg 1.7 mg/kg D5453 in Light Hydrocarbons, SparkIgnition Engine Fuel, Diesel Engine Fuel, and Engine Oil by UltravioletFluorescence. ASTM D130 Corrosion - Copper Strip Biodiesel-Cu 1aCorrosion 50° C. (122° F.)/3 hr ASTM Cloud Point Cloud Point 6 ° C.D2500 ASTM Micro Carbon Residue Average Micro <0.10 Wt % D4530 MethodCarbon Residue ASTM D664 Acid Number of Petroleum Procedure Used AProducts by Potentiometric Acid Number 0.20 mg Titration KOH/g ASTMDetermination of Free and Free Glycerin <0.005 Wt % D6584 Total Glycerinin B-100 Total Glycerin 0.123 Wt % Biodiesel Methyl Esters By GasChromatography ASTM Additive Elements in Phosphorus 0.000200 Wt % D4951Lubricating Oils by ICP-AES ASTM Distillation of Petroleum IBP 248 ° C.D1160 Products at Reduced Pressure AET @ 5% 336 ° C. Recovery AET @ 10%338 ° C. Recovery AET @ 20% 339 ° C. Recovery AET @ 30% 340 ° C.Recovery AET @ 40% 342 ° C. Recovery AET @ 50% 344 ° C. Recovery AET @60% 345 ° C. Recovery AET @ 70% 347 ° C. Recovery AET @ 80% 349 ° C.Recovery AET @ 90% 351 ° C. Recovery AET @ 95% 353 ° C. Recovery FBP 362° C. % Recovered 98.5 % % Loss 1.5 % % Residue 0.0 % Cold Trap Volume0.0 ml IBP 248 ° C. EN 14112 Determination of Oxidation OxidationStability >12 hr Stability (Accelerated Operating Temp 110 ° C.Oxidation Test) (usually 110 deg C.) ASTM Density of Liquids by DigitalAPI Gravity @ 60° F. 29.5 °API D4052 Density Meter ASTM D Determinationof Ignition Derived Cetane >61.0 6890 Delay (ID) and Derived Number(DCN) Cetane Number (DCN)

The lipid profile of the biodiesel was highly similar to the lipidprofile of the feedstock oil. Other oils provided by the methods andcompositions of the invention can be subjected to transesterification toyield biodiesel with lipid profiles including (a) at least 4% C8-C14;(b) at least 0.3% C8; (c) at least 2% C10; (d) at least 2% C12; and (3)at least 30% C8-C14.

The Cold Soak Filterability by the ASTM D6751 A1 method of the biodieselproduced was 120 seconds for a volume of 300 ml. This test involvesfiltration of 300 ml of B100, chilled to 40° F. for 16 hours, allowed towarm to room temp, and filtered under vacuum using 0.7 micron glassfiber filter with stainless steel support. Oils of the invention can betransesterified to generate biodiesel with a cold soak time of less than120 seconds, less than 100 seconds, and less than 90 seconds.

C. Production of Renewable Diesel

Degummed oil from Prototheca moriformis UTEX 1435, produced according tothe methods described above and having the same lipid profile as the oilused to make biodiesel in this Example, above, was subjected totransesterification to produce renewable diesel.

The oil was first hydrotreated to remove oxygen and the glycerolbackbone, yielding n-paraffins. The n-parrafins were then subjected tocracking and isomerization. A chromatogram of the material is shown inFIG. 1. The material was then subjected to cold filtration, whichremoved about 5% of the C18 material. Following the cold filtration thetotal volume material was cut to flash point and evaluated for flashpoint, ASTM D-86 distillation distribution, cloud point and viscosity.Flash point was 63° C.; viscosity was 2.86 cSt (centistokes); cloudpoint was 4° C. ASTM D86 distillation values are shown in Table 39:

TABLE 39 ASTM D86 distillation values. Readings in ° C.: VolumeTemperature IBP 173  5 217.4 10 242.1 15 255.8 20 265.6 30 277.3 40283.5 50 286.6 60 289.4 70 290.9 80 294.3 90 300 95 307.7 FBP 331.5

The T10-T90 of the material produced was 57.9° C. Methods ofhydrotreating, isomerization, and other covalent modification of oilsdisclosed herein, as well as methods of distillation and fractionation(such as cold filtration) disclosed herein, can be employed to generaterenewable diesel compositions with other T10-T90 ranges, such as 20, 25,30, 35, 40, 45, 50, 60 and 65° C. using triglyceride oils producedaccording to the methods disclosed herein.

The T10 of the material produced was 242.1° C. Methods of hydrotreating,isomerization, and other covalent modification of oils disclosed herein,as well as methods of distillation and fractionation (such as coldfiltration) disclosed herein, can be employed to generate renewablediesel compositions with other T10 values, such as T10 between 180 and295, between 190 and 270, between 210 and 250, between 225 and 245, andat least 290.

The T90 of the material produced was 300° C. Methods of hydrotreating,isomerization, and other covalent modification of oils disclosed herein,as well as methods of distillation and fractionation (such as coldfiltration) disclosed herein can be employed to generate renewablediesel compositions with other T90 values, such as T90 between 280 and380, between 290 and 360, between 300 and 350, between 310 and 340, andat least 290.

The FBP of the material produced was 300° C. Methods of hydrotreating,isomerization, and other covalent modification of oils disclosed herein,as well as methods of distillation and fractionation (such as coldfiltration) disclosed herein, can be employed to generate renewablediesel compositions with other FBP values, such as FBP between 290 and400, between 300 and 385, between 310 and 370, between 315 and 360, andat least 300.

Other oils provided by the methods and compositions of the invention canbe subjected to combinations of hydrotreating, isomerization, and othercovalent modification including oils with lipid profiles including (a)at least 4% C8-C14; (b) at least 0.3% C8; (c) at least 2% C10; (d) atleast 2% C12; and (3) at least 30% C8-C14.

Although this invention has been described in connection with specificembodiments thereof, it will be understood that it is capable of furthermodifications. This application is intended to cover any variations,uses, or adaptations of the invention following, in general, theprinciples of the invention and including such departures from thepresent disclosure as come within known or customary practice within theart to which the invention pertains and as may be applied to theessential features hereinbefore set forth.

Example 10: Engineering Microorganisms to Produce C18:2 and C18:3Glycerolipids

The synthesis of lipids in algae and plants starts with conversion ofGlucose or other carbon sources into acetyl CoA via the plastidicpyruvate dehydrogenase complex. Next, Acetyl CoA carboxylase (ACCase)utilizing bicarbonate as a substrate, generates the 3-C compound,malonyl CoA. β-ketoacyl-ACP (acyl carrier protein) synthase III (KASIII) then catalyzes the first condensation reaction between malonyl CoAand Acetyl CoA to produce a 4-C compound. Successive 2-C additionsthrough C16:0 are catalyzed by KAS I. The final 2-C extension to C18:0is catalyzed by KAS II. Thioesterases (TEs) terminate elongation off ofthe acyl-ACP. The soluble enzyme, Stearoyl ACP desaturase (SAD) hasactivity toward C18:0-ACP substrates and forms the double bond at the A9position resulting in oleate-ACP. The resulting C18:1 fatty acid isliberated from the ACP via the action of either an oleate or broadspecificity TE.

All fatty acids, once liberated from ACP in the plastid are transportedto the ER where lipid (TAG) biosynthesis occurs. Broadly speaking, thereare two routes for lipid biosynthesis in the ER of higher plants,however the two pathways no doubt share substrates at some level. Thefatty acyl CoA independent pathway transfers fatty acyl groups betweenphosphatidyl choline (P-choline) moieties employingacyllysophosphatidylcholine acyl transferases that may exhibit veryselective substrate specificites, ultimately transferring them todiacylglycerol (DAG). The enzyme diacylglycerol acyltransferase (DGAT)carries out the final transfer of fatty acyl groups from an acyl CoAsubstrate to DAG resulting in the final triacyl glycerol. The fatty acylCoA dependent pathway, on the other hand, transfers fatty acyl groupsusing fatty acyl CoAs as substrates onto glycerol-3-phosphate,lysophosphatidic acid (LPA) and DAG through the actions of glycerolphosphate acyltransferase (GPAT), lysophosphatidic acid acyltransferase(LPAAT) and DGAT, respectively.

Enzymes useful in engineering microorganisms to synthesize TAGscomprising C18:2 and C18:3 include β-ketoacyl-ACP synthase IIs (KAS II),stearoyl ACP desaturases (SADs), thioesterases, including oleatespecific thioesterases, fatty acid desaturates (FADs), and glycerolipiddesaturases, such as ω-6 fatty acid desaturases, ω-3 fatty aciddesaturases, or ω-6-oleate desaturases. These different enzymes can beoverexpressed in microorganisms either singly or in combination toincrease C18:2 or C18:3 fatty acid or TAG production. Increasing theexpression of KAS II enzyme activity pushes carbon accumulation frompalmitate (C16:0) toward stearate (C18:0) and beyond. The amino acidsequences of several candidate KAS II enzymes are shown below in Table40. The KAS II sequences disclosed are from higher plant species thatspecifically produce elevated levels of oleic, linoleic or linolenicfatty acids. A skilled artisan will be able to identify other genes forKAS II, including without limitation Jatropha curcas (GenBank AccessionNo. ABJ90469.2), Glycine max (GenBank Accession No. AAW88762.1), Elaeisoleifera (GenBank Accession No. ACQ41833.1), Arabidopsis thaliana(GenBank Accession No. AAL91174), Vitis vinifera (GenBank Accession No.CBI27767), and Gossypium hirsutum (GenBank Accession No. ADK23940.1).

TABLE 40 Exemplary KAS II enzymes. KAS II enzyme SEQ ID NO Ricinuscommunis SEQ ID NO: 175 Helianthus annus SEQ ID NO: 176 Brassica napusSEQ ID NO: 177 Glycine max SEQ ID NO: 178 P. moriformis SEQ ID NO: 179

Converting increased levels of stearates to oleic acid (C18:1) for theproduction of elevated levels of linoleic and linolenic fatty acids isachieved through microbial overexpression of one or more lipid pathwayenzymes. Two additional enzymatic activities that have utility inelevating the levels of unsaturates are the stearoyl ACP desaturases(SAD) and oleate specific thioesterases. Converting increased levels ofstearates (C18:0) to oleic acid through the action of one or both ofthese enzymes is first accomplished for the formation of linoleic andlinolenic fatty acids.

The amino acid sequences of exemplary SAD enzymes useful foroverexpression for elevating oleic acid levels are referenced in Table41. In addition, the endogenous SAD from P. moriformis (SEQ ID NO:180)is also effective for increasing C18:1 levels. The SAD sequencesdisclosed are from higher plant species that specifically produceelevated levels of oleic, linoleic or linolenic fatty acids. A skilledartisan will be able to identify other genes for SADs.

TABLE 41 Exemplary SAD enzymes. SAD enzyme SEQ ID NO GenBank ID No.Ricinus communis SEQ ID NO: 196 ACG59946.1 Helianthus annus SEQ ID NO:197 AAB65145.1 Brassica juncea SEQ ID NO: 198 AAD40245.1 Glycine max SEQID NO: 199 ACJ39209.1 Olea europaea SEQ ID NO: 200 AAB67840.1 Verniciafordii SEQ ID NO: 201 ADC32803.1

SAD enzymes have activity toward C18:0-ACP substrates and form thecarbon-carbon double bond at the A9 position resulting in oleate-ACP.The resulting C18:1 fatty acid is liberated from the ACP via the actionof either an oleate or broad specificity TE. We have shown in theexamples herein that the over expression of the Olea europaeastearoyl-ACP desaturase (Accession No: AAB67840.1; SEQ ID NO: 172) orthe Carthamus tinctorius ACP thioesterase (Accession No: AAA33019.1; SEQID NO: 195) results in increased accumulation of C18:1 fatty acids. Theamino acid sequences of exemplary oleate thioesterases useful forincreasing oleic fatty acids are referenced in Table 42. A skilledartisan will be able to identify other genes for oleate thioesterases.

TABLE 42 Exemplary thioesterases for elevated oleic fatty acidproduction. Thioesterase Enzyme SEQ ID NO GenBank ID No. Helianthusannus SEQ ID NO: 202 AAL79361.1 Brassica rapa SEQ ID NO: 203 AAC49002.1Jatropha curcas SEQ ID NO: 204 ABX82799.3 Zea mays SEQ ID NO: 205ACG40089.1 Zea mays SEQ ID NO: 206 ACG42559.1

Fatty acid desaturates are additional enzymes that have utility inincreasing accumulation of linoleic and linolenic fatty acids inmicrobes. In particular, two enzymatic activities, FAD 2 and FAD 3,provide increased accumulation of linoleic and linolenic fatty acids inmicrobes. The amino acid sequences of exemplary FAD 2 and FAD 3 enzymesare shown below in Table 43.

TABLE 43 Exemplary FAD 2 and FAD 3 enzymes. FAD 2 and FAD 3 enzymes SEQID NO Linus usitatissimum 12 desaturase SEQ ID NO: 181 Linususitatissimum 15 desaturase SEQ ID NO: 182 Linus usitatissimum 15desaturase SEQ ID NO: 183 Carthamus tinctorus 12 desaturase SEQ ID NO:184 Helianthus annus 12 desaturase SEQ ID NO: 185

In addition to those enzymes listed in Table 43, the amino acidsequences of exemplary Δ12 FAD enzymes are listed in Table 44. Other Δ12FAD enzymes suitable for overexpression in microorganisms are referencedin Table 45. The amino acid sequences of exemplary Δ15 FADs and otherenzymes useful for increasing the level of unsaturated fatty acids andTAGs are listed in Table 46. Additional glycerolipid desaturase enzymesare provided in Table 47.

TABLE 44 Exemplary Δ12 FAD enzymes for increasing linoleic fatty acidproduction. Δ12 FAD enzyme SEQ ID NO GenBank ID No. Carthamus tinctoriusSEQ ID NO: 207 ADM48790.1 Gossypium hirsutum SEQ ID NO: 208 CAA71199.1Glycine max SEQ ID NO: 209 BAD89862.1 Zea mays SEQ ID NO: 210 ABF50053.1Prototheca moriformis SEQ ID NO: 211 allele 1 Prototheca moriformis SEQID NO: 212 allele 2

TABLE 45 Additional Δ12 FAD enzymes suitable for overexpression inmicroorganisms to increase linoleic acid or linolenic acid. Δ12 FADenzymes GGenBank Accession No. Vernonia galamensis AAAF04094.1 Vernoniagalamensis AAAF04093.1 Wrightia tinctoria AADK47520.1 Olea europaeaAAAW63041.1 Vernicia fordii AAAN87573 Arabidopsis thaliana AAAA32782.1Camelina sativa AADU18247.1 Camelina sativa AADU18248.1 Camelina sativaAADU18249.1 Carthamus tinctorius AADK94440.1 Glycine max BBAD89862.1Glycine max DDQ532371.1 Gossypium hirsutum AAAL37484.1 Linumusitatissimum AACF49507.1 Linum usitatissimum AACF49508.1 Oenotherabiennis AACB47482 Saccharomyces cerevisiae NNP_011460.1 Zea maysAACG37433.1 Brassica rapa CCAD30827.1

TABLE 46 Exemplary Δ15 FAD enzymes for increasing linolenic fatty acidproduction Δ15 FAD enzyme SEQ ID NO GenBank ID No. Brassica napa SEQ IDNO: 213 AAA32994.1 Camelina sativa SEQ ID NO: 214 Camelina sativa SEQ IDNO: 215 Glycine max SEQ ID NO: 216 ACF19424.1 Vernicia fordii SEQ ID NO:217 AAF12821.1 Ricinus communis SEQ ID NO: 218 EEF36775.1 Linumusitatissimum SEQ ID NO: 219 ADV92272.1 Prototheca moriformis SEQ ID NO:220 allele 1 Prototheca moriformis SEQ ID NO: 221 allele 2

TABLE 47 Glycerolipid desaturases suitable for overexpression inmicroorganisms to increase linolenic acid or increase levels ofunsaturated TAGs. Glycerolipid desaturases GenBank Acession No. Glycinemax ACD69577.1 Glycine max cultivar volania ACS15381.1 Glycine sojaP48621.1 Arabidopsis thaliana NP_180559.1 Linum grandiflorum BAG70949.1Zea mays BAA22440.1 Olea europaea ABG88130.2 Jatropha curcas ABX82798.1Vernicia fordii CAB45155.1 Vernicia fordii AAD13527.1

The amino acid sequences disclosed herein are expressed in microbesutilizing the methods disclosed herein. Coding sequences can beoptimized for expression in the microorganism. For example, forexpression in P. moriformis, preferred codon usage as disclosed in Table2 herein are utilized.

Example 11: Engineering Microorganisms for Increased Production ofLinolenic Unsaturated Fatty Acids and Glycerolipids

As described in Example 10, Δ15 desaturase enzymes catalyze theformation of a double bond at position 15 of C18:2 (linoleic) fattyacids or fatty acyl molecules, thereby generating C18:3 (linolenic)fatty acids or fatty acyl molecules. Certain higher plant species,including Brassica napus (Bn), Camelina sativa (Cs), and Linumusitatissimum, which produce oils rich in linolenic unsaturated fattyacids, are sources of genes encoding Δ15 desaturases that can beexpressed in microorganisms to affect fatty acid profiles. This exampledescribes the use of polynucleotides that encode Δ15 desaturases enzymesto engineer microorganisms in which the fatty acid profile of thetransformed microorganism has been enriched in linolenic acid.

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis UTEX 1435, strain A, was transformed withindividually with each of the plasmid constructs listed in Table 49according to the biolistic transformation methods detailed in Example 2.Each construct contained a 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84)homologous recombination targeting sequences (flanking the construct) tothe 6S genomic region for integration into the nuclear genome and a S.cerevisiae suc2 sucrose invertase coding region under the control of C.reinhardtii β-tubulin promoter/5′UTR and Chlorella vulgaris nitratereductase 3′ UTR. This S. cerevisiae suc2 expression cassette is listedas SEQ ID NO: 159 and the sucrose invertase gene served as a selectionmarker. All protein-coding regions were codon optimized to reflect thecodon bias inherent in Prototheca moriformis UTEX 1435 nuclear genes, inaccordance with Table 2. The coding regions of desaturase genes fromBrassica napus (Bn FAD3, GenBank Accession No. AAA32994), Camelinasativa FAD-7, and Linum usitatissimum (Lu FAD3A and Lu FAD3B, GenBankAccession Nos. ABA02172 and ABA02173) were each under the control of thePrototheca moriformis Amt03 promoter/5′UTR (SEQ ID NO: 89) and C.vulgaris nitrate reductase 3′UTR. A FLAG® epitope sequence was encodedin the N-terminus cytoplasmic loop of the recombinant desaturase genesequences.

TABLE 49 Plasmid constructs used to transform Protheca moriformis (UTEX1435) strain A. Plasmid Construct Relevant Sequence Elements SEQ ID NO:pSZ2124 6S::Crβtub:ScSuc2:Cvnr::PmAmt03: SEQ ID NO: 2223xFlag-BnFad3:Cvnr::6S pSZ2125 6S::Crβtub:ScSuc2:Cvnr::PmAmt03: SEQ IDNO: 223 3xFlag-CsFad7-1:Cvnr::6S pSZ21266S::Crβtub:ScSuc2:Cvnr::PmAmt03: SEQ ID NO: 224 3xFlag-LuFad3A:Cvnr::6SpSZ2127 6S::Crβtub:ScSuc2:Cvnr::PmAmt03: SEQ ID NO: 2253xFlag-LuFad3B:Cvnr::6S

Each of the constructs pSZ2124, pSZ2125, pSZ2126, and pSZ2127 wastransformed individually into strain A. Primary transformants wereselected on agar plates containing sucrose as a sole carbon source.Individual transformants were clonally purified and grown at pH 7.0under conditions suitable for lipid production, similar those disclosedin Example 1. Lipid samples were prepared from dried biomass from eachtransformant. 20-40 mg of dried biomass from each was resuspended in 2mL of 5% H₂SO₄ in MeOH, and 200 ul of toluene containing an appropriateamount of a suitable internal standard (C19:0) was added. The mixturewas sonicated briefly to disperse the biomass, then heated at 70-75° C.for 3.5 hours. 2 mL of heptane was added to extract the fatty acidmethyl esters, followed by addition of 2 mL of 6% K₂CO₃ (aq) toneutralize the acid. The mixture was agitated vigorously, and a portionof the upper layer was transferred to a vial containing Na₂SO₄(anhydrous) for gas chromatography analysis using standard FAME GC/FID(fatty acid methyl ester gas chromatography flame ionization detection)methods. Fatty acid profiles were analyzed using standard fatty acidmethyl ester gas chromatography flame ionization (FAME GC/FID) detectionmethods. The resulting fatty acid profiles (expressed as Area % of totalfatty acids) from a set of representative clones arising from strain Atransformations of pSZ2124, pSZ2125, pSZ2126 and pSZ2127 are shown inTable 50. For comparison, fatty acid profiles of lipids obtained fromuntransformed strain A control cells are additionally presented in Table50.

TABLE 50 Unsaturated C18:1, C18:2, and C18:3 fatty acid profiles ofPrototheca moriformis cells engineered to express exogenous desaturaseenzymes of higher plants. % of Total Fatty Acids Strain Sample C18:1C18:2 C18:3 strain A 1 55.68 7.99 0.63 untransformed 2 55.31 8.16 0.7pSZ2124 Transformant 1 60.42 1.62 7.69 Brassica napus Transformant 259.7 0.6 8.49 FAD3 Transformant 3 60.56 1.19 8.15 Transformant 4 59.850.8 7.9 pSZ2125 Transformant 1 57.11 9.45 1.4 Camelina Transformant 257.5 8.56 1.39 sativa FAD7 Transformant 3 56.27 8.78 1.39 Transformant 452.57 9.39 1.7 pSZ2126 Transformant 1 58.97 0.84 9.67 Linum Transformant2 57.93 1.36 11.92 usitatissimum Transformant 3 59.37 0.58 10.33 FAD3ATransformant 4 59.05 0.49 10.24 pSZ2127 Linum Transformant 1 59.6 1.678.67 usitatissimum Transformant 2 59.73 1.02 8.6 FAD3B Transformant 360.04 1.6 8.74 Transformant 4 58.57 0.89 9.05

The untransformed Prototheca moriformis (UTEX 1435) strain A strainexhibits a fatty acid profile comprising less than 1% C18:3 fatty acids.In contrast, fatty acid profiles of strain A expressing higher plantfatty acid desaturase enzymes showed increased composition of C18:3fatty acids, ranging from about 2 to 17 fold increase. Engineeredstrains expressing FAD3A or FAD3B of Linum usitatissimum or the FAD3gene product of Brassica napus showed the greatest degree of C18:3increase (Table 50). The ratio of 18:3 to total C18 unsaturates wasabout 1% in the untransformed strains and ranged from about 2% to 17% inthe transformed strains. The ratio of 18:2 to total C18:0 was about12-13% in the untransformed strains and ranged from about 1% to 15% inthe transformed strains with the lowest levels in the FAD3Atransformant. These data demonstrate the utility and effectiveness ofpolynucleotides permitting exogenous expression of Δ15 desaturase fattyacid desaturase enzymes to alter the fatty acid profile of engineeredmicroorganisms, and in particular in increasing the concentration of18:3 fatty acids in microbial cells.

Example 12: Engineering Microorganisms for Increased Production ofStearic Acid and Stearate Through a Hairpin RNA Approach

Stearoyl ACP desaturase (SAD) enzymes are a part of the lipid synthesispathway. They function to introduce double bonds into fatty acyl chains.For example, SAD enzymes catalyze the synthesis of C18:1 fatty acidsfrom C18:0 fatty acids (stearic acid). As shown in Example 6,interruption of SAD2 alleles of Prototheca moriformis through targetedgene disruption resulted in measurable increases in C18:0 fatty acidlevels in the fatty acid profiles of the engineered microorganism. Thisexample describes the use of polynucleotides encoding hairpin RNAs thatdown-regulate the expression of SAD2 to engineer microorganisms in whichthe fatty acid profile of the transformed microorganism has beenenriched in saturated C18:0 fatty acids.

Four constructs, pSZ2139-pSZ2142, listed in Table 51, were designed toattenuate expression of the Prototheca moriformis SAD2 gene product.Each construct contained a different nucleic acid sequence encoding ahairpin RNA targeted against the Prototheca moriformis SAD2 mRNAtranscript, with a stem length ranging in size from 180 to 240 basepairs, as well as 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologousrecombination targeting sequences (flanking the construct) to the 6Sgenomic region for integration into the nuclear genome and a S.cerevisiae suc2 sucrose invertase coding region under the control of C.reinhardtii β-tubulin promoter/5′UTR and Chlorella vulgaris nitratereductase 3′ UTR. This S. cerevisiae suc2 expression cassette is listedas SEQ ID NO: 159 and served as a selection marker. The polynucleotidesequence encoding the SAD2 RNA hairpin of each construct was under thecontrol of the C. reinhardtii β-tubulin promoter/5′UTR and C. vulgarisnitrate reductase 3′UTR.

TABLE 51 Plasmid constructs used to transform Protheca moriformis (UTEX1435) strain A. Plasmid Construct Relevant Sequence Elements SEQ ID NO:SZ2139 6S::Crβtub:ScSuc2:Cvnr:Crβtub:PmSAD2- SEQ ID NO: hairpin AhpA:Cvnr::6S 226 SZ2140 6S::Crβtub:ScSuc2:Cvnr:Crβtub:PmSAD2- SEQ ID NO:hairpin B hpB:Cvnr::6S 227 SZ2141 6S::Crβtub:ScSuc2:Cvnr:Crβtub:PmSAD2-SEQ ID NO: hairpin C hpC:Cvnr::6S 228 SZ21426S::Crβtub:ScSuc2:Cvnr:Crβtub:PmSAD2- SEQ ID NO: hairpin D hpD:Cvnr::6S229

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis UTEX 1435, strain A, was transformed individuallywith the plasmid constructs listed in Table 51 according to biolistictransformation methods detailed in Example 2. Primary transformants wereselected on agar plates containing sucrose as a sole carbon source,clonally purified, and grown under standard lipid production conditions.Fatty acid profiles were determined using direct transesterificationmethods as described in Example 11. The resulting fatty acid profiles(expressed as Area % of total fatty acids) from a set of representativeclones arising from transformations of strain A with pSZ2139, pSZ2140,pSZ2141, and pSZ2142 are shown in Table 52, below. For comparison, fattyacid profiles of lipids obtained from untransformed strain A controlcells are additionally presented in Table 52.

TABLE 52 C18:0, C18:1, and C18:2 fatty acid profiles of Protothecamoriformis cells engineered to express hairpin RNA constructs targetingstearoyl ACP desaturase gene/gene products. Strain/ % Ratio Plasmid %Total Fatty Acids C18 Sat:C18 Construct Transformant C18:0 C18:1 C18:2UnSat strain A Untransformed 2.77 60.74 7.27 4 strain Transformant I6.39 51.69 9.06 11 A/pSZ2139 Transformant 2 5.49 52.89 9.25 9 hairpin ATransformant 3 3.39 56.12 8.85 5 Transformant 4 3.24 54.55 8.62 5 strainTransformant I 22.14 36.14 8.13 50 A/pSZ2140 Transformant 2 17.19 41.178.31 35 hairpin B Transformant 3 9.45 49.81 8.79 16 Transformant 4 5.6153.8 9.02 9 strain Transformant I 20.7 40.96 6.45 44 A/pSZ2141Transformant 2 16.33 45.57 7.31 31 hairpin C Transformant 3 13.43 44.799.04 25 Transformant 4 12.7 46.25 9.98 23 Transformant 5 8.47 50.65 9.1214 strain Transformant 1 26.99 30.93 8.31 69 A/pSZ2142 Transformant 210.96 47.27 9.9 19 hairpin D Transformant 3 8.64 50.77 11.7 14Transformant 4 7.67 49.76 9.39 13

The data presented in Table 52 show a clear impact of the expression ofSAD2 hairpin RNA constructs on the C18:0 and C18:1 fatty acid profile ofthe host organism. The fatty acid profiles of strain A transformantscomprising SAD2 hairpin RNA constructs demonstrated an increase in thepercentage of saturated C18:0 fatty acids with a concomitant diminutionof unsaturated C18:1 fatty acids. Fatty acid profiles of theuntransformed strain comprise about 3% C18:0. Fatty acid profiles of thetransformed strains comprise greater than 3% to almost 27% C18:0. Theratio of C18:0 to total C18 unsaturates was about 4% in theuntransformed strains and ranged from about 5% to 69% in the transformedstrains. These data illustrate the successful expression and use ofpolynucleotide SAD RNA hairpin constructs in Prototheca moriformis toalter the percentage of saturated fatty acids in the engineered hostmicrobes, and in particular in increasing the concentration of C18:0fatty acids and decreasing C18:1 fatty acids in microbial cells.

Example 13: Altering Fatty Acid Profiles of Microalgae ThroughOverexpression of β-Ketoacyl-ACP Synthase II Genes

β-ketoacyl-ACP synthase II (KASII) catalyzes the 2-carbon extension ofC16:0-ACP to C18:0-ACP during fatty acid biosynthesis. Plasmidconstructs were created to assess whether the fatty acid profile of ahost cell can be affected as a result of expression of a KASII gene.Sources of KASII gene sequences were selected from Protheca moriformisUTEX 1435 or from higher plants (Glycine max GenBank Accession No.AAW88763, Helianthus annus GenBank Accession No. ABI18155, and Ricinuscommunis GenBank Accession No. AAA33872).

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis UTEX 1435, strain A, was transformed individuallywith one of the following plasmid constructs in Table 53 using themethods of Example 2. Each construct comprised 5′ (SEQ ID NO: 82) and 3′(SEQ ID NO: 84) homologous recombination targeting sequences (flankingthe construct) to the 6S genomic region for integration into the nucleargenome and a S. cerevisiae suc2 sucrose invertase coding region underthe control of C. reinhardtii β-tubulin promoter/5′UTR and Chlorellavulgaris nitrate reductase 3′ UTR. This S. cerevisiae suc2 expressioncassette is listed as SEQ ID NO: 29 and served as a selection marker.For each construct, the KASII coding region was under the control of thePrototheca moriformis Amt03 promoter/5′UTR (SEQ ID NO: 37) and C.vulgaris nitrate reductase 3′UTR. The native transit peptide of eachKASII enzyme was replaced with the Chlorella protothecoides stearoyl-ACPdesaturase transit peptide (SEQ ID NO: 54). All protein coding regionswere codon optimized to reflect the codon bias inherent in Protothecamoriformis UTEX 1435 nuclear genes in accordance with Table 2.

TABLE 53 Plasmid constructs used to transform Protheca moriformis (UTEX1435) strain A. Plasmid Source of KASII Construct enzyme SequenceElements SEQ ID. NO: SZ1747 Glycine max (Glm) 6S::β- SEQ ID NO: 230tub:suc2:nr::Amt03:S106SAD: GlmKASII:nr::6S SZ1750 Helianthus annuus6S::β- SEQ ID NO: 231 (Ha) tub:suc2:nr::Amt03:S106SAD: HaKASII:nr::6SSZ1754 Ricinus communis 6S:β- SEQ ID NO: 232 (Rc)tub:suc2:nr::Amt03:S106SAD: RcKASII:nr::6S SZ2041 Protheca moriformis6S::β- SEQ ID NO: 233 (Pm) tub:suc2:nr:Amt03:S106SAD: PmKASII:nr::6S

Relevant restriction sites in the construct6S::β-Tub:suc2:nr::Amt03:S106SAD:PmKASII:nr::6S are indicated inlowercase, bold and underlining and are 5′-3′ BspQ 1, Kpn I, Xba I, MfeI, BamH I, EcoR I, Spe I, Asc I, Cla I, Sac I, BspQ I, respectively.BspQI sites delimit the 5′ and 3′ ends of the transforming DNA. Bold,lowercase sequences represent genomic DNA from strain A that permittargeted integration at the 6S locus via homologous recombination.Proceeding in the 5′ to 3′ direction, the C. reinhardtii β-tubulinpromoter driving expression of the yeast sucrose invertase gene(conferring the ability of strain A to metabolize sucrose) is indicatedby boxed text. The initiator ATG and terminator TGA for invertase areindicated by uppercase, bold italics while the coding region isindicated in lowercase italics. The Chlorella vulgaris nitrate reductase3′ UTR is indicated by lowercase underlined text followed by anendogenous amt03 promoter of P. moriformis, indicated by boxeditalicized text. The Initiator ATG and terminator TGA codons of thePmKASII are indicated by uppercase, bold italics, while the remainder ofthe gene is indicated by bold italics. The Chlorella protothecoides S106stearoyl-ACP desaturase transit peptide is located between the initiatorATG and the Asc I site. The C. vulgaris nitrate reductase 3′ UTR isagain indicated by lowercase underlined text followed by the strain A 6Sgenomic region indicated by bold, lowercase text. The relevantnucleotide sequence of the construct6S::β-tub:suc2:nr::Amt03:S106SAD:PmKASII:nr::6S is provided in thesequence listings as SEQ ID. NO: 234. The codon-optimized sequence ofPmKASII comprising a Chlorella protothecoides S106 stearoyl-ACPdesaturase transit peptide is provided the sequence listings as SEQ ID.NO: 235. SEQ ID NO: 236 provides the protein translation of SEQ ID NO.235.

gctcttcgccgccgccactcctgctcgagcgcgcccgcgcgtgcgccgccagcgccttggccttttcgccgcgctcgtgcgcgtcgctgatgtccatcaccaggtccatgaggtctgccttgcgccggctgagccactgcttcgtccgggcggccaagaggagcatgagggaggactcctggtccagggtcctgacgtggtcgcggctctgggagcgggccagcatcatctggctctgccgcaccgaggccgcctccaactggtcctccagcagccgcagtcgccgccgaccctggcagaggaagacaggtgaggggggtatgaattgtacagaacaaccacgagccttgtctaggcagaatccctaccagtcatggctttacctggatgacggcctgcgaacagctgtccagcgaccctcgctgccgccgcttctcccgcacgcttctttccagcaccgtgatggcgcgagccagcgccgcacgctggcgctgcgcttcgccgatctgaggacagtcggggaactctgatcagtctaaacccccttgcgcgttagtgttgccatcctttgcagaccggtgagagccgacttgttgtgcgccaccccccacaccacctcctcccagaccaattctgt

atgacgaacgagacgtccgaccgccccctggtgcacttcacccccaacaagggctggatgaacgaccccaacggcctgtggtacgacgagaaggacgccaagtggcacctgtacttccagtacaacccgaacgacaccgtctgggggacgcccttgttctggggccacgccacgtccgacgacctgaccaactgggaggaccagcccatcgccatcgccccgaagcgcaacgactccggcgccttctccggctccatggtggtggactacaacaacacctccggcttcttcaacgacaccatcgacccgcgccagcgctgcgtggccatctggacctacaacaccccggagtccgaggagcagtacatctcctacagcctggacggcggctacaccttcaccgagtaccagaagaaccccgtgctggccgccaactccacccagttccgcgacccgaaggtcttctggtacgagccctcccagaagtggatcatgaccgcggccaagtcccaggactacaagatcgagatctactcctccgacgacctgaagtcctggaagctggagtccgcgttcgccaacgagggcttcctcggctaccagtacgagtgccccggcctgatcgaggtccccaccgagcaggaccccagcaagtcctactgggtgatgttcatctccatcaaccccggcgccccggccggcggctccttcaaccagtacttcgtcggcagcttcaacggcacccacttcgaggccttcgacaaccagtcccgcgtggtggacttcggcaaggactactacgccctgcagaccttcttcaacaccgacccgacctacgggagcgccctgggcatcgcgtgggcctccaactgggagtactccgccttcgtgcccaccaacccctggcgctcctccatgtccctcgtgcgcaagttctccctcaacaccgagtaccaggccaacccggagacggagctgatcaacctgaaggccgagccgatcctgaacatcagcaacgccggcccctggagccggttcgccaccaacaccacgttgacgaaggccaacagctacaacgtcgacctgtccaacagcaccggcaccctggagttcgagctggtgtacgccgtcaacaccacccagacgatctccaagtccgtgttcgcggacctctccctctggttcaagggcctggaggaccccgaggagtacctccgcatgggcttcgaggtgtccgcgtcctccttcttcctggaccgcgggaacagcaaggtgaagttcgtgaaggagaacccctacttcaccaaccgcatgagcgtgaacaaccagcccttcaagagcgagaacgacctgtcctactacaaggtgtacggcttgctggaccagaacatcctggagctgtacttcaacgacggcgacgtcgtgtccaccaacacctacttcatgaccaccgggaacgccctgggctccgtg

gtatcgacacactctggacgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaggatcccgcgtctcgaacagagcgcgcagaggaacgctgaaggtctcgcctctgtcgcacctcagcgcggcatacaccacaataaccacctgacgaatgcgcttggttcttcgtccattagcgaagcgtccggttcacacacgtgccacgttggcgaggtggcaggtgacaatgatcggtggagctgatggtcgaaacgttcac

taaggcagcagcagctcggatagtatcgacacactctggacgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaaagcttaattaa gagctcttgttttccagaaggagttgctccttgagcctttcattctcagcctcgataacctccaaagccgctctaattgtggagggggttcgaatttaaaagcttggaatgttggttcgtgcgtctggaacaagcccagacttgttgctcactgggaaaaggaccatcagctccaaaaaacttgccgctcaaaccgcgtacctctgctttcgcgcaatctgccctgttgaaatcgccaccacattcatattgtgacgcttgagcagtctgtaattgcctcagaatgtggaatcatctgccccctgtgcgagcccatgccaggcatgtcgcgggcgaggacacccgccactcgtacagcagaccattatgctacctcacaatagttcataacagtgaccatatttctcgaagctccccaacgagcacctccatgctctgagtggccaccccccggccctggtgcttgcggagggcaggtcaaccggcatggggctaccgaaatccccgaccggatcccaccacccccgcgatgggaagaatctctccccgggatgtgggcccaccaccagcacaacctgctggcccaggcgagcgtcaaaccataccacacaaatatccttggcatcggccctgaattccttctgccgctctgctacccggtgcttctgtccgaagcaggggttgctagggatcgctccgagtccgcaaacccttgtcgcgtggcggggcttgttcgagctt gaagagc

Upon individual transformation of each plasmid construct into strain A,positive clones were selected on agar plates comprising sucrose as thesole carbon source. As in the previous examples, primary transformantswere clonally purified and grown under standard lipid productionconditions at pH 7 and lipid samples were prepared from dried biomassfrom each transformant. Fatty acid profiles were determined using directtransesterification methods as described in Example 11. The resultingfatty acid profiles (expressed as Area % of total fatty acids) from aset of representative clones arising from transformations of strain AFatty acid profiles (expressed as Area %) of several positivetransformants as compared to those of untransformed strain A controlsare summarized for each plasmid construct in Table 54 below.

TABLE 54 Fatty acid profiles of Prototheca moriformis cells engineeredto overexpress KAS II genes. Plasmid KASII Construct Source Transformant% C14:0 % C16:0 % C18:0 % C18:1 % C18:2 None no over- 1 1.36 28.69 2.9256.36 8.16 expression 2 1.35 28.13 3.57 55.63 8.79 3 1.22 25.74 2.8260.6 7.31 4 1.22 25.74 2.82 60.6 7.31 pSZ1747 Glycine 1 2.23 25.34 2.6957.35 9.53 max 2 2.18 25.46 2.74 57.35 9.46 3 2.18 25.33 2.89 57.34 9.54 2.2 25.69 2.66 57.28 9.43 5 2.17 25.38 3.03 56.99 9.72 pSZ1750 H.annus 1 2.43 26.82 2.72 55.17 9.87 2 2.44 27.14 2.62 54.89 9.81 3 2.6126.9 2.67 54.43 10.25 4 1.96 30.32 2.87 53.87 8.26 5 2.55 27.64 2.9853.82 10.07 pSZ1754 Ricinus 1 1.84 24.41 2.89 59.26 9.08 communis 2 1.325.04 2.81 58.75 9.65 3 1.27 25.98 2.76 58.33 9.22 4 1.95 25.34 2.7758.15 9.22 5 1.3 26.53 2.75 57.87 9.09 pSZ2041 P. 1 1.63 11.93 3.6270.95 9.64 moriformis 2 1.85 11.63 3.34 69.88 10.93 3 1.84 12.01 3.8169.56 10.45 4 1.63 14.22 3.72 68.86 9.6 5 1.67 15.04 3.05 68.63 9.24

A clear diminution of C16:0 chain lengths with a concomitant increase inC18:1 length fatty acids was observed upon overexpression of thePrototheca moriformis (UTEX 1435) KASII gene further codon optimizedusing the codon frequency denoted in Table 2 using pSZ2041. Similarfatty acid profile changes were observed upon transformation ofconstructs expressing the Prototheca moriformis (UTEX 1435) KASII genedriven by a β-tublin promoter.

These results show that exogenous overexpression of a codon optimizedPrototheca lipid biosynthesis gene can alter the fatty acid profile ofgenetically engineered microalgae. In particular, overexpression of aKASII gene can increase the percentage of C18 fatty acids from about 68%in the untransformed cells to about 84%.

Example 14: Altering the Levels of Mid-Chain Fatty Acids in EngineeredPrototheca Through Targeted Knockout of a KASI Allele

β-ketoacyl-ACP synthase I (KASI) catalyzes 2-carbon extensions of C4:0,C6:0, C8:0, C10:0, C12:0, and C14:0 fatty acyl-ACP molecules duringfatty acid biosynthesis. In this example, a knockout plasmid construct,pSZ2014, was created to assess the impact on the fatty acid profile of ahost cell upon targeted disruption of a KASI genetic locus.

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis UTEX 1435, strain A, was transformed the pSZ2014construct using the biolistic transformations methods described inExample 2. pSZ2014 comprised the S. cerevisiae suc2 invertase expressioncassette under control of the C. reinhardtii β-tubulin promoter andChlorella vulgaris nitrate reductase 3′ UTR, flanked on either side byKASI gene-specific homology regions to target the construct forintegration into the KASI locus of the Prototheca moriformis genome.This S. cerevisiae suc2 expression cassette is listed as SEQ ID NO: 159and served as a selection marker. Relevant sequences for the targetingregions to the KASI locus for nuclear genome integration are shown belowand listed in SEQ ID NO: 238 and SEQ ID NO: 239. Relevant restrictionsites in pSZ2014, indicated in lowercase, bold and underlining, are5′-3′ BspQ 1, Kpn I, AscI, Xho I, Sac I, BspQ I, respectively are shownin the sequence below. BspQI sites delimit the 5′ and 3′ ends of thetransforming DNA. Bold, lowercase sequences represent genomic DNA fromstrain A that permit targeted integration at KASI locus via homologousrecombination. Proceeding in the 5′ to 3′ direction, the C. reinhardtiib-tubulin promoter driving the expression of the codon-optimized yeastsucrose invertase gene (conferring the ability of strain A to metabolizesucrose) is indicated by boxed text. The initiator ATG codon andterminator TGA codon for suc2 invertase are indicated by uppercase, bolditalics while the coding region is indicated in lowercase italics. TheChlorella vulgaris nitrate reductase 3′ UTR is indicated by lowercaseunderlined text. The transforming sequence of pSZ2014 is shown below andlisted as SEQ ID NO: 237.

gctcttcgctcaccgcgtgaattgctgtcccaaacgtaagcatcatcgtggctcggtcacgcgatcctggatccggggatcctagaccgctggtggagagcgctgccgtcggattggtggcaagtaagattgcgcaggttggcgaagggagagaccaaaaccggaggctggaagcgggcacaacatcgtattattgcgtatagtagagcagtggcagtcgcatttcgaggtccgcaacggatctcgcaagctcgctacgctcacagtaggagaaaggggaccactgcccctgccagaatggtcgcgaccctctccctcgccggccccgcctgcaacacgcagtgcgtatccggcaagcgggctgtcgccttcaaccgcccccatgttggcgtccgggctcgatcaggtgcgctgaggggggtttggtgtgcccgcgcctctgggcccgtgtcggccgtgcggacgtggggccctgggcagtggatcagcagggtttgcgtgcaaatgcctataccggcgattgaatagcgatgaacgggatacggttgcgctcactccatgcccatgcgaccccgtttctgtccgccagccgtggtcg

ctggccggcttcgccgccaagatcagcgcctccatgacgaacgagacgtccgaccgccccctggtgcacttcacccccaacaagggctggatgaacgaccccaacggcctgtggtacgacgagaaggacgccaagtggcacctgtacttccagtacaacccgaacgacaccgtctgggggacgcccttgttctggggccacgccacgtccgacgacctgaccaactgggaggaccagcccatcgccatcgccccgaagcgcaacgactccggcgccttctccggctccatggtggtggactacaacaacacctccggcttcttcaacgacaccatcgacccgcgccagcgctgcgtggccatctggacctacaacaccccggagtccgaggagcagtacatctcctacagcctggacggcggctacaccttcaccgagtaccagaagaaccccgtgctggccgccaactccacccagttccgcgacccgaaggtcttctggtacgagccctcccagaagtggatcatgaccgcggccaagtcccaggactacaagatcgagatctactcctccgacgacctgaagtcctggaagctggagtccgcgttcgccaacgagggcttcctcggctaccagtacgagtgccccggcctgatcgaggtccccaccgagcaggaccccagcaagtcctactgggtgatgttcatctccatcaaccccggcgccccggccggcggctccttcaaccagtacttcgtcggcagcttcaacggcacccacttcgaggccttcgacaaccagtcccgcgtggtggacttcggcaaggactactacgccctgcagaccttcttcaacaccgacccgacctacgggagcgccctgggcatcgcgtgggcctccaactgggagtactccgccttcgtgcccaccaacccctggcgctcctccatgtccctcgtgcgcaagttctccctcaacaccgagtaccaggccaacccggagacggagctgatcaacctgaaggccgagccgatcctgaacatcagcaacgccggcccctggagccggttcgccaccaacaccacgttgacgaaggccaacagctacaacgtcgacctgtccaacagcaccggcaccctggagttcgagctggtgtacgccgtcaacaccacccagacgatctccaagtccgtgttcgcggacctctccctctggttcaagggcctggaggaccccgaggagtacctccgcatgggcttcgaggtgtccgcgtcctccttcttcctggaccgcgggaacagcaaggtgaagttcgtgaaggagaacccctacttcaccaaccgcatgagcgtgaacaaccagcccttcaagagcgagaacgacctgtcctactacaaggtgtacggcttgctggaccagaacatcctggagctgtacttcaacgacggcgacgtcgtgtccaccaacacctacttcatgaccaccgggaacgccctgggctccgtgaacatgacgacgggggtgg

atggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaggatcgtagagctccacctgcatccgcctggcgctcgaggacgccggcgtctcgcccgacgaggtcaactacgtcaacgcgcacgccacctccaccctggtgggcgacaaggccgaggtgcgcgcggtcaagtcggtctttggcgacatgaagggcatcaagatgaacgccaccaagtccatgatcgggcactgcctgggcgccgccggcggcatggaggccgtcgccacgctcatggccatccgcaccggctgggtgcaccccaccatcaaccacgacaaccccatcgccgaggtcgacggcctggacgtcgtcgccaacgccaaggcccagcacaaaatcaacgtcgccatctccaactccttcggcttcggcgggcacaactccgtcgtcgcctttgcgcccttccgcgagtaggcggagcgagcgcgcttggctgaggagggaggcggggtgcgagccctttggctgcgcgcgatactctccccgcacgagcagactccacgcgcctgaatctacttgtcaacgagcaaccgtgtgttttgtccgtggccattcttattatttctccgactgtggccgtactctgtttggctgtgcaagcacc gaagagc

Upon transformation of plasmid construct pSZ2014 into strain A, positiveclones were selected on plates with sucrose as the sole carbon source.Primary transformants were clonally purified and grown under standardlipid production conditions. Lipid samples were prepared from driedbiomass from each transformant. Fatty acid profiles were determinedusing direct transesterification methods as described in Example 11.Fatty acid profiles (expressed as Area % of total fatty acid) of severalpositive transformants, compared to those of untransformed strain Acontrols, are summarized for in Table 55 below.

TABLE 55 Fatty acid profiles of engineered Prototheca moriformis cellscomprising a selectable marker to disrupt an endogenous KASI allele.Transformant % C14:0 % C16:0 % C18:0 % C18:1 % C18:2 strain Auntransformed 1.22 25.61 2.82 60.76 7.44 control strain A Transformant 11.65 32.55 2.17 53.99 7.43 pSZ2014 Transformant 2 2.25 30.04 2.57 55.867.12 Transformant 3 3.51 31.22 1.90 53.85 7.00 Transformant 4 4.09 31.512.57 53.14 6.21 Transformant 5 4.68 34.47 1.94 49.75 6.49 Transformant 65.68 37.98 1.83 44.76 6.75 Transformant 7 5.82 37.82 1.93 44.84 6.44

As shown in Table 55 above, targeted interruption of a KASI alleleimpacted the fatty acid profiles of transformed microorganisms. Fattyacid profiles of strain A comprising the pSZ2014 transformation vectorshowed increased composition of C14:0 and C16:0 fatty acids with aconcomitant decrease in C18:1 fatty acids. In all transformantis, C18:0fatty acids were reduced. In some transformations, interruption of theKASI allele further resulted in a fatty acid profile comprisingdecreased percentages of C18:2 fatty acids relative to the fatty acidprofile of the untransformed strain A organism.

Thus, we increased the percentage of total C14 fatty acids by about 35%to 400% and the percentage of C16 fatty acids by about 30 to 50% bydisruption of an endogenous KASI.

These data demonstrate the utility of targeted gene interruption of anendogenous KASI allele to alter the fatty acid profile of a hostmicrobe.

Example 15: Combining Genetic Modification Approaches to Alter FattyAcid Profiles in Prototheca

In this example, the combination of genetic modifications to knockout aKASII allele and concomitantly overexpress an exogenous thioesteraseexhibiting a preference for hydrolysis of mid chain fatty acids isdemonstrated in a microorganism to alter the fatty acid profile of thehost organism.

A classically mutagenized (for higher oil production) strain ofPrototheca moriformis (UTEX 1435), strain C, was initially transformedwith the plasmid construct pSZ1283 according to biolistic transformationmethods detailed in Example 2. pSZ1283 (SEQ ID NO: 256), previouslydescribed in PCT Application Nos. PCT/US2011/038463 andPCT/US2011/038463, comprises the coding sequence of the Cuphea wrightiiFATB2 (CwTE2) thioesterase, 5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84)homologous recombination targeting sequences (flanking the construct) tothe 6S genomic region for integration into the nuclear genome, and a S.cerevisiae suc2 sucrose invertase coding region under the control of C.reinhardtii β-tubulin promoter/5′UTR and Chlorella vulgaris nitratereductase 3′ UTR. This S. cerevisiae suc2 expression cassette is listedas SEQ ID NO: 159 and served as a selection marker. The CwTE2 codingsequence was under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR(SEQ ID NO: 32). The protein coding regions of CwTE2 and suc2 were codonoptimized to reflect the codon bias inherent in Prototheca moriformisUTEX 1435 nuclear genes in accordance with Table 2.

Upon transformation of pSZ1283 into strain C, positive clones wereselected on agar plates with sucrose as the sole carbon source. Primarytransformants were then clonally purified and a single transformant,strain B, was selected for further genetic modification. Thisgenetically engineered strain was transformed with a plasmid construct,pSZ2110 (SEQ ID NO: 240), to interrupt the KASII allele 1 locus.pSZ2110, written as KASII′5::CrbTub:NeoR:nr::KASII-′3, comprised aneomycin resistance (NeoR) expression cassette, conferring resistance toG418, under control of the C. reinhardtii □-tubulin promoter andChlorella vulgaris nitrate reductase 3′ UTR, flanked on either side byKASII gene-specific homology regions to target the construct forintegration into the KASII locus of the Prototheca moriformis genome.The relevant restriction sites in the pSZ2110 construct from 5′-3′ areBspQ 1, KpnI, XbaI, MfeI, BamHI, EcoRI, SpeI, Xho, Sac I, and BspQI areindicated in lowercase, bold, and underlined formats. BspQI sitesdelimit the 5′ and 3′ ends of the transforming DNA. Bold, lowercasesequences at the 5′ and 3′ ends of the transforming construct representgenomic DNA from UTEX 1435 that target integration to the KASII allele 1locus via homologous recombination. The C. reinhardtii □-tubulin isindicated by lowercase, boxed text. The initiator ATG and terminator TGAfor NeoR are indicated by uppercase italics, while the coding region isindicated with lowercase italics.

gctcttcgctggcctgttgccggacgatccgtgtcgtcgagactgcattttgttttgggtgtggggctggggtactggatggcttgagggcatgactttttctgatggagaagattgcaatgagatcatttgggtcgtctatttgtttgctgtgcaagagggtttactggtatctggcaccagcttttggcccgtgcccgtttgatggacgcgtgacaggcaggcgtcctggaaagcacagacaccgtacgtacgaccttgacctcccccccttctccacacggcaggtgcgaggctgcccacggcgtcgaggcgggcggtgcgccgggcatggtcccgcatcgcgcgcgcggcggccgcggccgacgcaaaccccgcccgccctgagcgccgcgtggtcatcacgggccagggcgtggtgaccagcctgggccagacgatcgagcagttttacagcagcctgctggagggcgtgagcggcatctcgcagatacagaagttcgacaccacgggctacacgacgacgatcgcgggcgagatcaagtcgctgcagctggacccgtacgtgcccaagcgctgggcgaagcgcgtggacgacgtgataaagtacgtctacatcgcgggcaagcaggcgctggagagcgccggcctgccgatcgaggcggcggggctggcgggcgcggggctggacccggcgctgtgcggcgtgctcatcggcaccgccatggcgggcatgacgtctttcg

aatatcaATGatcgagcaggacggcctccacgccggctcccccgccgcctgggtggagcgcctgttcggctacgactgggcccagcagaccatcggctgctccgacgccgccgtgttccgcctgtccgcccagggccgccccgtgctgttcgtgaagaccgacctgtccggcgccctgaacgagctgcaggacgaggccgcccgcctgtcctggctggccaccaccggcgtgccctgcgccgccgtgctggacgtggtgaccgaggccggccgcgactggctgctgctgggcgaggtgcccggccaggacctgctgtcctcccacctggcccccgccgagaaggtgtccatcatggccgacgccatgcgccgcctgcacaccctggaccccgccacctgccccttcgaccaccaggccaagcaccgcatcgagcgcgcccgcacccgcatggaggccggcctggtggaccaggacgacctggacgaggagcaccagggcctggcccccgccgagctgttcgcccgcctgaaggcccgcatgcccgacggcgaggacctggtggtgacccacggcgacgcctgcctgcccaacatcatggtggagaacggccgcttctccggcttcatcgactgcggccgcctgggcgtggccgaccgctaccaggacatcgccctggccacccgcgacatcgccgaggagctgggcggcgagtgggccgaccgcttcctggtgctgtacggcatcgccgcccccgactcccagcgcatcgccttctaccgcctgctggacgagttcttcTGAcaattggcagcagcagctcggatagtatcgacacactctggacgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaggatccactagttctagagcggccgccaccgcggtg gagctcggcggcgtgcgcaagatgaaccccttttgcatccccttctccatctccaacatgggcggcgcgatgctggcgatggacatcggcttcatgggccccaactactccatctccacggcctgcgcgacgggcaactactgcatcctgggcgcggcggaccacatccggcgcggcgacgcaaacgtgatgctggccggcggcgcggacgcggccatcatcccctcgggcatcggcggcttcatcgcgtgcaaggcgctgagcaagcgcaacgacgagcccgagcgcgcgagccggccctgggacgccgaccgcgacggcttcgtcatgggcgagggcgccggcgtgctggtgctggaggagctggagcacgccaagcgccgcggcgcgaccattttggctgaattagttggcggcgcggccacctcggacgcgcaccacatgaccgagcccgacccgcagggccgcggcgtgcgcctctgcctcgagcgcgcgctcgagcgcgcgcgcctcgcgcccgagcgcgtcggctacgtcaacgcgcacggcaccagcacgcccgcgggcgacgtggccgagtaccgcgccatccgcgccgtcatcccgcaggactcactacgcatcaactccacaaagtccatgatcgggcacctgctcggcggcgccggcgcggtcgaggccgtggccgccatccaggccctgcgcaccggctggctccaccccaacttgaacctcgagaaccccgcgcctggcgtcgaccccgtcgtgctcgtgggctctt cc

Upon transformation of strain B with pSZ2110, positive clones wereselected on selective agar plates containing G418. Primary transformantswere then clonally purified and grown on sucrose as a carbon sourceunder standard lipid production conditions at both pH 5.0 and at pH 7.0.Lipid samples were prepared from dried biomass from each transformant asdescribed in Example 11. Fatty acid profiles (expressed as Area % oftotal fatty acids) of 5 positive transformants (T1-T5), profiles ofstrain B grown on sucrose as a sole carbon source (U1), and profiles ofuntransformed UTEX 1435 (U1) grown on glucose as a sole carbon source,are presented in Table 56 below.

TABLE 56 Fatty acid profiles of Prototheca moriformis (UTEX 1435)multiply engineered to ablate an endogenous KASII gene product and toexpress a Cuphea wrightii thioesterase. Strain UTEX strain Fatty 1435 Bstrain B pSZ2011 acid pH U1 U1 T1 T2 T3 T4 T5 % C10:0 pH 5.0 0.01 * 0.020.03 0.03 0.03 0.07 pH 7.0 0.01  5.35 4.94 4.79 4.70 4.10 4.12 % C12:0pH 5.0 0.04 * 0.09 0.39 0.41 0.41 0.86 pH 7.0 0.04 27.06 25.31 25.0325.02 23.54 23.47 % C14:0 pH 5.0 1.30 * 0.92 1.13 1.14 1.15 1.50 pH 7.01.56 15.20 14.49 14.22 14.50 15.84 15.85 % C16:0 pH 5.0 25.89 * 36.0735.05 35.35 35.23 35.05 pH 7.0 29.80 13.89 14.96 14.88 15.11 22.62 22.94% C18:0 pH 5.0 2.84 * 1.76 1.79 1.84 1.82 1.80 pH 7.0 3.00  1.44 1.571.71 1.49 1.37 1.33 % C18:1 pH 5.0 60.34 * 49.82 50.21 49.97 50.01 49.13pH 7.0 54.96 28.57 29.84 30.45 30.27 24.18 23.96 % C18:2 pH 5.0 7.40 *8.39 8.59 8.47 8.52 8.75 pH 7.0 8.15  6.85 7.19 7.16 7.15 6.51 6.65 *Not tested

As shown in Table 56, the impact of expression of CwTE2 in Protothecamoriformis (UTEX 1435) strain B is a marked change in the fatty acidprofiles of the transformed microorganisms. Fatty acid profiles ofstrain B strains expressing CwTE2 and cultured at pH 7.0, to promoteexpression of CwTE2 from the Amt03 promoter, showed increasedcomposition of C10:0, C12:0, and C14:0 fatty acids with a concomitantdecrease in the composition of C16:0 and C18:1 fatty acids relative tothe fatty acid profile of untransformed UTEX 1435. Subsequentmodification of strain B to interrupt a KASII allele, encoding an enzymethat catalyzes the 2-carbon extension of C16:0 to C18:0 fatty acids,resulted in an increase in C16:0 fatty acids with a concomitant decreasein C18:1 fatty acids present in the lipid profile of the newlyengineered strain when grown at pH 5.0. Propagation of transformants atpH 5.0 illustrates the impact of the KASII allele knockout apart fromthe thioesterase contribution to the altered fatty acid profiles, as thepH of this culture medium is not optimal for activity of the Amt03promoter. Upon lipid production at pH 7.0, thereby expressing CwTE2,pSZ2011 transformants exhibited a fatty acid profile increased incomposition of C10:0, C12:0, and C14:0 fatty acids with a concomitantdecrease in the composition of C16:0 and C18:1 fatty acids relative tothe profile of the UTEX 1435 strain. Some pSZ2011 transformants whencultured at pH 7.0 exhibited a fatty acid profile enriched in C16:0fatty acids with still a further decrease in the composition of C18:1fatty acids relative to the fatty acid profile of their parent strainstrain B cultured at pH 7.0.

These data demonstrate the utility of multiple genetic modifications toimpact the fatty acid profile of a host organism. Further, this exampleillustrates the use of recombinant polynucleotides to target geneinterruption of an endogenous KASII allele to alter the fatty acidprofile of a host microbe.

Example 16: Combining Genetic Modification Approaches to Alter thePalmitic Acid Composition of Prototheca

In this example, the combination of genetic modifications to knockout aKASII allele and concomitantly overexpress an exogenous thioesteraseexhibiting preferential specificity for hydrolysis of C14 and C16 fattyacids is demonstrated in a microorganism to alter the fatty acid profileof the host organism.

A classically mutagenized (for higher oil production) strain ofPrototheca moriformis (UTEX 1435), strain A, was transformed with theplasmid construct pSZ2004 according to the biolistic transformationmethods detailed in Example 2. pSZ2004, written asKASII_5′_btub-SUC2-nr_2X_Amt03-Ch16TE2-nr_KASII_3′, comprised the codingsequence of the Cuphea hookeriana fatty acyl-ACP thioesterase (Ch16TE2,GenBank #Q39513), 5′ and 3′ homologous recombination targeting sequences(flanking the construct) for targeted integration at the KASII locus ofthe nuclear genome, and a S. cerevisiae suc2 sucrose invertase codingregion under the control of C. reinhardtii β-tubulin promoter/5′UTR andChlorella vulgaris nitrate reductase 3′ UTR. Ch16TE2 is a thioesterasethat show preferential specificity for C14 and C16 fatty acids. This S.cerevisiae suc2 expression cassette is listed as SEQ ID NO: 159 andserved as a selection marker. The Ch16TE coding sequence was under thecontrol of the Prototheca moriformis Amt03 promoter/5′UTR (SEQ ID NO:89) repeated in tandem, and C. vulgaris nitrate reductase 3′UTR. Theprotein coding regions of Ch16TE and suc2 were codon optimized toreflect the codon bias inherent in Prototheca moriformis UTEX 1435nuclear genes in accordance with Table 2. pSZ2004 is presented in thesequence listing as SEQ ID NO: 249.

Upon transformation with pSZ2004, primary transformants were selected onplates containing sucrose as a sole carbon source. Individualtransformants were clonally purified and grown under standard lipidproduction conditions at pH 7.0, similar to the conditions as disclosedin Example 1. Fatty acid profiles were analyzed using standard fattyacid methyl ester gas chromatography flame ionization (FAME GC/FID)detection methods as described in Example 11. The resulting fatty acidprofile (expressed as Area % of total fatty acid) from a representativeclone arising from the transformations of the transformation vectorpSZ2004 is shown in Table 57. The fatty acid profile of lipids obtainedfrom the untransformed strain grown under lipid production conditionscomprising glucose as a sole carbon source are additionally presented inTable 57.

TABLE 57 Fatty acid profiles of Prototheca moriformis (UTEX 1435)multiply engineered to ablate an endogenous KASII gene product and toexpress a Cuphea hookeriana thioesterase. Fatty Acid UTEX 1435 pSZ2004 %C10:0 0.01 0.00 % C12:0 0.04 0.09 % C14:0 1.27 6.42 % C16:0 27.20 69.97% C18:0 3.85 1.84 % C18:1 58.70 13.69 % C18:2 7.18 7.15

As shown in Table 57 above, targeted interruption of a KASII allele withan expression cassette for expression of a selectable marker and aC14/C16 preferring thioesterase impacted the fatty acid profile oftransformed microorganism. The fatty acid profile of the straincomprising the pSZ2004 transformation vector showed increasedcomposition of C14:0 and C16:0 fatty acids with a concomitant decreasein C18:0 and C18:1 fatty acids. The untransformed Prototheca moriformis(UTEX 1435) strain exhibited a fatty acid profile comprising about 27%C16 fatty acids and about 58% C18:1 fatty acids. In contrast, fatty acidprofiles of the strain disrupted at the KASII locus by a cassetteenabling expression of a Cuphea hookeriana fatty acyl-ACP thioesteraseand a selectable marker comprised about 70% C16 fatty acids and about14% fatty acids. The level of C16:0 was increased by over 2.5 fold.These data show that the genetic modifications of exogenous geneoverexpression and endogenous gene ablation can be combined to alterfatty acid profiles in host organisms.

For comparison, fatty acid profiles of a strain disrupted at the KASIIlocus, by a cassette enabling expression of a sucrose invertase geneprovided a strain with about 35% C16 fatty acids and about 50% C18:1fatty acids.

These data demonstrate the utility and effectiveness of polynucleotidespermitting exogenous expression of a thioesterase enzyme to alter thefatty acid profile of engineered microorganisms, in particular inincreasing the concentration of C14 and C16 fatty acids andconcomitantly, through targeted disruption of a KASII allele with saidpolynucleotides, effecting the decrease of C18:0 and C18:1 fatty acidsin microbial cells.

Example 17: Engineering Microorganisms to Produce Linoleic UnsaturatedFatty Acids and Glycerolipids

Certain Δ12 fatty acid desaturase enzymes can catalyze the formation ofa double bond in C18:1 fatty acids or fatty acyl molecules, therebygenerating C18:2 (linoleic) fatty acids or fatty acyl molecules. Certainplant species, including Gossypium hirsutum, Carthamus ticntorius,Glycine max, Helianthus annus, and Zea mays, which produce oils rich inlinoleic unsaturated fatty acids, are sources of genes encoding Δ12desaturases that can be expressed in microorganisms to affect fatty acidprofiles. This example describes the use of polynucleotides that encodeΔ12 desaturases enzymes to engineer microorganisms in which the fattyacid profile of the transformed microorganism has been enriched inlinoleic acid.

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis UTEX 1435, strain A, was transformed with one of thefollowing plasmid constructs listed in Table 58 according to biolistictransformation methods detailed in Example 2. Each construct contained5′ (SEQ ID NO: 82) and 3′ (SEQ ID NO: 84) homologous recombinationtargeting sequences (flanking the construct) to the 6S genomic regionfor integration into the nuclear genome and a S. cerevisiae suc2 sucroseinvertase coding region under the control of C. reinhardtii β-tubulinpromoter/5′UTR and Chlorella vulgaris nitrate reductase 3′ UTR. This S.cerevisiae suc2 expression cassette is listed as SEQ ID NO: 159 andserved as a selection marker. All protein coding regions were codonoptimized to reflect the codon bias inherent in Prototheca moriformisUTEX 1435, in accordance with Table 2. The coding regions of desaturasegenes from Gossypium hirsutum (Gh, GenBank Accession No. CAA71199),Carthamus ticntorius (Ct GenBank Accession No. ADM48789), Glycine max(Gm, GenBank Accession No. BAD89862), Helianthus annus (Ha, GenBankAccession No. AAL68983), and Zea mays (Zm, GenBank Accession No.ABF50053) were each under the control of the Prototheca moriformis Amt03promoter/5′UTR (SEQ ID NO: 89) and C. vulgaris nitrate reductase 3′UTR.

TABLE 58 Plasmid constructs used to transform Protheca moriformis (UTEX1435) strain A. Plasmid Construct Relevant Sequence Elements SEQ ID NO:pSZ2150 6S::Crβtub:ScSuc2:Cvnr:PmAmt03:CtFad2-2:Cvnr::6S SEQ ID NO: 241pSZ2151 6S::Crβtub:ScSuc2:Cvnr:PmAmt03:GlmFad2-2:Cvnr::6S SEQ ID NO: 242pSZ2152 6S::Crβtub:ScSuc2:Cvnr::PmAmt03:HaFad2:Cvnr::6S SEQ ID NO: 243pSZ2153 6S::Crβtub:ScSuc2:Cvnr::PmAmt03:ZmFad2:Cvnr::6S SEQ ID NO: 244pSZ2172 6S::Crβtub:ScSuc2:Cvnr::PmAmt03:GhFad2:Cvnr::6S SEQ ID NO: 245

Each of the constructs listed in Table 58 was transformed individuallyinto strain A. Primary transformants were selected on plates containingsucrose as a sole carbon source. Individual transformants were clonallypurified and grown under standard lipid production conditions at pH 7.0,similar to the conditions as disclosed in Example 1. Fatty acid profileswere analyzed using standard fatty acid methyl ester gas chromatographyflame ionization (FAME GC/FID) detection methods described in Example11. The resulting fatty acid profiles from a set of representativeclones arising from the corresponding strain A transformations of Table58 are shown in Table 59. For comparison, fatty acid profiles of lipidsobtained from untransformed strain A control cells are additionallypresented in Table 59.

TABLE 59 C18:1, C18:2, and C18:3 fatty acid profiles of Protothecamoriformis cells engineered to express exogenous FAD desaturase enzymes.Total C18 % C18 unsaturates (% polyunsatu- % of Total Fatty Acids ofTotal Fatty rates/total C18 Strain Sample C18:1 C18:2 C18:3 Acids)unsaturates strain A Unstransformed 55.37 8.18 0.7 64.25 13.82 strain ATransformant 1 58.29 11.96 0.75 71 17.90 pSZ2150 Ct Transformant 2 59.0010.29 0.84 70.13 15.87 FAD2-2 Transformant 3 52.41 10.36 1.16 63.9318.02 Transformant 4 56.77 10.17 0.8 67.74 16.19 Transformant 5 57.1910.15 0.79 68.13 16.06 strain A Transformant 1 58.09 10.32 0.86 69.2716.14 pSZ2151 Glm Transformant 2 59.6 11.87 0.86 72.33 17.60 FAD2-2Transformant 3 58.93 11.54 0.83 71.3 17.35 Transformant 4 58.4 12.29 0.971.59 18.42 Transformant 5 58.27 10.8 0.83 69.9 16.64 Transformant 658.85 10.48 0.82 70.15 16.11 strain A Transformant 1 59.30 10.02 0.8270.14 15.45 pSZ2152 Ha Transformant 2 58.45 9.87 0.81 69.13 15.45 FAD2Transformant 3 59.38 9.89 0.79 70.06 15.24 Transformant 4 59.54 9.790.81 70.14 15.11 Transformant 5 59.07 9.92 0.82 69.81 15.38 Transformant6 59.57 10.02 0.55 70.14 15.07 strain A Transformant 1 64.30 11.18 0.8976.37 15.80 pSZ2153 Zm Transformant 2 58.54 10.49 0.88 69.91 16.26 FAD2Transformant 3 58.80 9.95 0.81 69.56 15.47 Transformant 4 56.18 10.811.16 68.15 17.56 Transformant 5 58.82 10.02 0.83 69.67 15.57Transformant 6 58.72 10.06 0.86 69.64 15.68 strain A Transformant 155.71 10.85 0.84 67.4 17.34 pSZ2172 Transformant 2 56.12 10.29 0.7567.16 16.44 Gh-FLAG-FAD2 Transformant 3 54.14 12 0.96 67.1 19.31Transformant 4 55.72 11.68 0.75 68.15 18.24

The untransformed Prototheca moriformis (UTEX 1435) strain exhibits afatty acid profile comprising less than 8.5% C18:2 fatty acids. As shownin Table 59. the lipid profiles of strain A strains expressing higherplant fatty acid desaturase enzymes showed increased C18:2 fatty acids.Total C18 unsaturated fatty acids increased from about 64% to about67-72%. Similarly, the ratio of total C18 polyunsaturated fatty acids(C18:2 and C18:3) to total combined C18 unsaturated fatty acids (C18:1,C18:2 and C18:3) increased from less than 14% to over 19%. These datademonstrate the utility and effectiveness of polynucleotides permittingexogenous expression of Δ12 desaturase fatty acid desaturase enzymes toalter the fatty acid profile of engineered microorganisms.

Example 18: Altering the Levels of Fatty Acids of Engineered MicrobesThrough Multiple Allelic Disruption of a Fatty Acid Desaturase

This example describes the use of a transformation vector to disrupt theFADc loci of Prototheca moriformis with a transformation cassettecomprising a selectable marker and sequence encoding an exogenous SADenzyme to engineer microorganisms in which the fatty acid profile of thetransformed microorganism has been altered.

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis (UTEX 1435), strain C, was transformed with thetransformation construct pSZ1499 (SEQ ID NO: 246) according to biolistictransformation methods detailed in Example 2. pSZ1499 comprisednucleotide sequence of the Olea europaea stearoyl-ACP desaturase gene,codon-optimized for expression in Protheca moriformis UTEX 1435. ThepSZ1499 expression construct contained 5′ (SEQ ID NO: 247) and 3′ (SEQID NO: 248) homologous recombination targeting sequences (flanking theconstruct) to the FADc genomic region for integration into the nucleargenome and a S. cerevisiae suc2 sucrose invertase coding region underthe control of C. reinhardtii β-tubulin promoter/5′UTR and Chlorellavulgaris nitrate reductase 3′ UTR. This S. cerevisiae suc2 expressioncassette is listed as SEQ ID NO: 159 and served as a selection marker.The Olea europaea stearoyl-ACP desaturase coding region was under thecontrol of the Prototheca moriformis Amt03 promoter/5′UTR (SEQ ID NO:89) and C. vulgaris nitrate reductase 3′UTR, and the native transitpeptide was replaced with the Chlorella protothecoides stearoyl-ACPdesaturase transit peptide (SEQ ID NO: 49). The entire O. europaea SADexpression cassette was termed pSZ1499 and can be written asFADc5′_btub-Suc2-nr_amt03-S106SAD-OeSAD-nr-FADc3′.

Primary transformants were selected on plates containing sucrose as asole carbon source. Individual transformants were clonally purified andgrown under standard lipid production conditions at pH 7.0, similar tothe conditions as disclosed in Example 1. Fatty acid profiles wereanalyzed using standard fatty acid methyl ester gas chromatography flameionization (FAME GC/FID) detection methods as described in Example 11.The resulting fatty acid profiles from a set of representative clonesarising from the transformations of the transformation vector are shownin Table 60. Fatty acid profiles of lipids obtained from theuntransformed strain C strain grown under lipid production conditionscomprising glucose as a sole carbon source (pH 5.0) are additionallypresented in Table 60.

TABLE 60 Fatty acid profiles of Prototheca moriformis (UTEX 1435)multiply engineered to knockout endogenous FADc alleles and to expressan O. europaea stearoyl-ACP desaturase. % Strain Transformant % C16:0 %C18:0 % C18:1 C18:2 strain C untransformed 28.50 3.72 57.70 7.04 strainC untransformed 28.57 3.69 57.61 7.07 strain C Transformant 1 20.37 1.1374.38 0.01 pSZ1499 Transformant 2 19.98 1.16 74.60 0.00 Transformant 320.10 1.16 74.70 0.00 Transformant 4 21.13 1.21 73.86 0.00 Transformant5 19.95 1.11 74.58 0.00 Transformant 6 20.20 1.14 74.61 0.00Transformant 7 20.72 1.15 74.15 0.00 Transformant 8 20.06 1.11 74.440.00 Transformant 9 19.86 1.18 74.88 0.00

As shown in Table 60, transformation of strain C with pSZ1499 impactsthe fatty acid profiles of the transformed microbes. The untransformedPrototheca moriformis (UTEX 1435) strain C strain exhibits a fatty acidprofile comprising less than 60% C18:1 fatty acids and greater than 7%C18:2 fatty acids. In contrast, strain C strains transformed withpSZ1499 exhibited fatty acid profiles with an increased composition ofC18:1 fatty acids and a concomitant decrease in C18:0 and C18:2 fattyacids. C18:2 fatty acids were undetected in the fatty acid profiles ofstrain C transformed with pSZ1499. The absence of detectable C18:2 fattyacids in pSZ1499 transformants indicated that the transformation withpSZ1499, bearing homologous recombination targeting sequences forintegration into multiple FADc genomic loci, had abolished FAD activity.

Southern blot analysis was conducted to verify that multiple FADcalleles were interrupted by the pSZ1499 transformation vector. GenomicDNA was extracted from strain C and pSZ1499 transformants using standardmolecular biology methods. DNA from each sample was run on 0.8% agarosegels after digestion with the restriction enzyme PstI. DNA from this gelwas transferred onto a Nylon+ membrane (Amersham), which was thenhybridized with a P32-labeled polynucleotide probe corresponding to FADc3′ region. FIG. 3 shows maps of the pSZ1499 transformation cassette, thetwo sequenced FADc alleles of Prototheca moriformis (UTEX 1435), and thepredicted sizes of the alleles disrupted by the pSZ1499 transformationvector. FADc allele 1 comprises a PstI restriction site, whereas FADcallele 2 does not. Integration of the SAD cassette would introduce aPstI restriction site into the disrupted FADc allele, resulting in a ˜6kb fragment resolved on the Southern, regardless of which allele wasdisrupted. FIG. 4 shows the results of Southern blot analysis. Ahybridization band at ˜6 kb is detected in both transformants. Nosmaller hybridization bands, that would be indicative of uninterruptedalleles, were detected. These results indicate that both FADc alleleswere disrupted by pSZ1499.

The ablation of both alleles of the FADc fatty acid desaturase with aSAD expression cassette results in fatty acid profiles comprising about74% C18:1. Collectively, these data demonstrate the utility andeffectiveness of polynucleotides permitting knockout of FAD alleles andconcomitant exogenous expression of stearoyl-ACP desaturase enzymes toalter the fatty acid profile of engineered microorganisms.

Example 19: Characteristics of Processed Oil Produced from EngineeredMicroorganisms

Methods and effects of transforming Prototheca moriformis (UTEX 1435)with transformation vector pSZ1500 (SEQ ID NO: 250) have been previouslydescribed in PCT Application Nos. PCT/US2011/038463 andPCT/US2011/038463.

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis (UTEX 1435), strain C, was transformed with thetransformation construct pSZ1500 according to biolistic transformationmethods detailed in Example 2. Primary transformants were selected onagar plates containing sucrose as a sole carbon source, clonallypurified, and a single engineered line, strain D was selected foranalysis. Strain D was grown as described herein. Hexane extraction ofthe oil from the generated biomass was then performed using standardmethods, and the resulting triglyceride oil was determined to be free ofresidual hexane. Other methods of extraction of oil from microalgaeusing an expeller press are described in PCT Application No.PCT/US2010/31108 and are hereby incorporated by reference.

Oil extracted from biomass of strain D was then refined, bleached, anddeodorized using well known vegetable oil processing methods. Theseprocedures generated an oil sample, RBD469, which was subjected to anumber of analytical testing protocols according to methods definedthrough the American Oil Chemists' Society, the American Society forTesting and Materials, and the International Organization forStandardization. The results of these analyses are summarized below inTable 60.

TABLE 60 Analytical results for oil sample RBD469. Method Number TestDescription Results Units AOCS Ca 3a-46 Insoluble impurities <0.01 %AOCS Ca 5a-40 Free Fatty Acids (Oleic) 0.02 % AOCS Ca 5a-40 Acid Value0.04 mg KOH/g AOCS CA 9f-57 Neutral oil 98.9 % D97 Cloud Point −15 degC. D97 Pour Point −18 deg C. Karl Fischer Moisture 0.01 % AOCS Cc 13d-55Chlorophyll <0.01 ppm (modified) Iodine Value 78.3 g I₂/100 g AOCS Cd8b-90 Peroxide Value 0.31 meq/kg ISO 6885 p-Anisidine Value 0.65 AOCS Cc18-80 Dropping Melting point 6.2 deg C. (Mettler) AOCS Cd 11d-96Tricylglicerides 98.6 % AOCS Cd 11d-96 Monoglyceride <0.01 % AOCS Cd11d-96 Diglicerides 0.68 % AOCS Cd 20-91 Total Polar Compounds 2.62 %IUPAC, 2.507 and Oxidized & Polymerized 17.62 % 2.508 TricylgliceridesAOCS Cc 9b-55 Flash Point 244 deg C. AOCS Cc 9a-48 Smoke Point 232 degC. AOCS Cd 12b-92 Oxidataive Stability Index 31.6 hours Rancimat (110°C.) AOCS Ca 6a-40 Unsaponified Matter 2.28 %

The same lot of Prototheca moriformis strain D RBD469 oil was analyzedfor trace element content, solid fat content, and Lovibond coloraccording to AOCS methods. Results of these analyses are presented belowin Table 61, Table 62, and Table 63.

TABLE 61 ICP Elemental Analysis of RBD469 oil. Method Number TestDescription Results in ppm AOCS Ca 20-99 and Phosphorus 1.09 AOCS Ca17-01 Calcium 0.1 (modified) Magnesium 0.04 Iron <0.02 Sulfur 28.8Copper <0.05 Potassium <0.50 Sodium <0.50 Silicon 0.51 Boron 0.06Aluminum <0.20 Lead <0.20 Lithium <0.02 Nickel <0.20 Vanadium <0.05 Zinc<0.02 Arsenic <0.20 Mercury <0.20 Cadmium <0.03 Chromium <0.02 Manganese<0.05 Silver <0.05 Titanium <0.05 Selenium <0.50 UOP779 Chloride organic<1 UOP779 Chloride inorganic 7.24 AOCS Ba 4e-93 Nitrogen 6.7

TABLE 62 Solid Fat Content of RBD469 Oil Method Number Solid Fat ContentResult AOCS Cd 12b-93 Solid Fat Content 10° C. 0.13% AOCS Cd 12b-93Solid Fat Content 15° C. 0.13% AOCS Cd 12b-93 Solid Fat Content 20° C.0.28% AOCS Cd 12b-93 Solid Fat Content 25° C. 0.14% AOCS Cd 12b-93 SolidFat Content 30° C. 0.08% AOCS Cd 12b-93 Solid Fat Content 35° C. 0.25%

TABLE 63 Lovibond Color of RBD469 Oil Method Number Color Result UnitAOCS Cc 13j-97 red 2 unit AOCS Cc 13j-97 yellow 27 unit

RBD469 oil was subjected to transesterification to produce fatty acidmethyl esters (FAMEs). The resulting fatty acid methyl ester profile ofRBD469 is shown in Table 64:

TABLE 64 Fatty acid methyl ester Profile of RBD469 Oil Fatty Acid Area %C10 0.01 C12:0 0.04 C14:0 0.64 C15:0 0.08 C16:0 8.17 C16:1 iso 0.39C16:1 0.77 C17:0 0.08 C18:0 1.93 C18:1 85.88 C18:1 0.05 C18:2 0.05 C20:00.3 C20:1 0.06 C20:1 0.44 C22:0 0.11 C23:0 0.03 C24:0 0.1 Total FAMEsIdentified 99.13

Example 20: Engineered Microalgae with Altered Fatty Acid Profiles

As described above, integration of heterologous genes to knockout orknockdown specific endogenous lipid pathway enzymes in Protothecaspecies can alter the fatty acid profiles of the engineered microbe. Inthis example, plasmid constructs were created to assess whether thelipid profile of a host cell can be affected as a result of a knockoutor knockdown of an endogenous fatty acyl-ACP thioesterase gene, FATA1.

A. Altering Lipid Profiles by Knockout of an Endogenous Protothecamoriformis Thioesterase Gene

A classically mutagenized (for higher oil production) derivative ofProtheca moriformis UTEX 1435, strain A, was transformed with one of thefollowing plasmid constructs in Table 65 using the methods of Example 2.Each construct contained a region for integration into the nucleargenome to interrupt the endogenous FATA1 gene and a S. cerevisiae suc2sucrose invertase coding region under the control of C. reinhardtiiβ-tubulin promoter/5′UTR and Chlorella vulgaris nitrate reductase 3′UTR. This S. cerevisiae suc2 expression cassette is listed as SEQ ID NO:159 and served as a selection marker. All protein coding regions werecodon optimized to reflect the codon bias inherent in Protothecamoriformis UTEX 1435 nuclear genes in accordance with Table 2. Relevantsequences for the targeting regions for the FATA1 gene used for nucleargenome integration are shown below.

Description SEQ ID NO: 5′ sequence for integration into FATA1 locus SEQID NO: 251 3′ sequence for integration into FATA1 locus SEQ ID NO: 252

TABLE 65 Plasmid constructs used to transform Protheca moriformis (UTEX1435) strain A. Plasmid Construct Sequence Elements 1FATA1-CrbTub_yInv_nr-FATA1 2 FATA1-CrbTub_yInv_nr::amt03_CwTE2_nr-FATA1

Relevant restriction sites in the construct FATA1-CrbTub_yInv_nr-FATA1(SEQ ID NO: 253) are indicated in lowercase, bold and underlining andare 5′-3′ BspQ 1, Kpn I, Asc I, Mfe I, Sac I, BspQ I, respectively.BspQI sites delimit the 5′ and 3′ ends of the transforming DNA. Bold,lowercase sequences represent genomic DNA from strain A that permittargeted integration at FATA1 locus via homologous recombination.Proceeding in the 5′ to 3′ direction, the C. reinhardtii β-tubulinpromoter driving the expression of the yeast sucrose invertase gene(conferring the ability of strain A to metabolize sucrose) is indicatedby boxed text. The initiator ATG and terminator TGA for invertase areindicated by uppercase, bold italics while the coding region isindicated in lowercase italics. The Chlorella vulgaris nitrate reductase3′ UTR is indicated by lowercase underlined text followed by the strainA FATA1 genomic region indicated by bold, lowercase text:

gctcttcggagtcactgtgccactgagttcgactggtagctgaatggagtcgctgctccactaaacgaattgtcagcaccgccagccggccgaggacccgagtcatagcgagggtagtagcgcgccatggcaccgaccagcctgcttgccagtactggcgtctcttccgcttctctgtggtcctctgcgcgctccagcgcgtgcgcttttccggtggatcatgcggtccgtggcgcaccgcagcggccgctgcccatgcagcgccgctgcttccgaacagtggcggtcagggccgcacccgcggtagccgtccgtccggaacccgcccaagagttttgggagcagcttgagccctgcaagatggcggaggacaagcgcatcttcctggaggagcaccggtgcgtggaggtccggggctgaccggccgtcgcattcaacgtaatcaatcgcatgatgatcagaggacacgaagtcttggtggcggtggccagaaacactgtccattgcaagggcatagggatgcgttccttcacctctcatttctcatttctgaatccctccctgctcactctttctcctcctccttc

ctgctgcaggccttcctgttcctgctggccggcttcgccgccaagatcagcgcctccatgacgaacgagacgtccgaccgccccctggtgcacttcacccccaacaagggctggatgaacgaccccaacggcctgtggtacgacgagaaggacgccaagtggcacctgtacttccagtacaacccgaacgacaccgtctgggggacgcccttgttctggggccacgccacgtccgacgacctgaccaactgggaggaccagcccatcgccatcgccccgaagcgcaacgactccggcgccttctccggctccatggtggtggactacaacaacacctccggcttcttcaacgacaccatcgacccgcgccagcgctgcgtggccatctggacctacaacaccccggagtccgaggagcagtacatctcctacagcctggacggcggctacaccttcaccgagtaccagaagaaccccgtgctggccgccaactccacccagttccgcgacccgaaggtcttctggtacgagccctcccagaagtggatcatgaccgcggccaagtcccaggactacaagatcgagatctactcctccgacgacctgaagtcctggaagctggagtccgcgttcgccaacgagggcttcctcggctaccagtacgagtgccccggcctgatcgaggtccccaccgagcaggaccccagcaagtcctactgggtgatgttcatctccatcaaccccggcgccccggccggcggctccttcaaccagtacttcgtcggcagcttcaacggcacccacttcgaggccttcgacaaccagtcccgcgtggtggacttcggcaaggactactacgccctgcagaccttcttcaacaccgacccgacctacgggagcgccctgggcatcgcgtgggcctccaactgggagtactccgccttcgtgcccaccaacccctggcgctcctccatgtccctcgtgcgcaagttctccctcaacaccgagtaccaggccaacccggagacggagctgatcaacctgaaggccgagccgatcctgaacatcagcaacgccggcccctggagccggttcgccaccaacaccacgttgacgaaggccaacagctacaacgtcgacctgtccaacagcaccggcaccctggagttcgagctggtgtacgccgtcaacaccacccagacgatctccaagtccgtgttcgcggacctctccctctggttcaagggcctggaggaccccgaggagtacctccgcatgggcttcgaggtgtccgcgtcctccttcttcctggaccgcgggaacagcaaggtgaagttcgtgaaggagaacccctacttcaccaaccgcatgagcgtgaacaaccagcccttcaagagcgagaacgacctgtcctactacaaggtgtacggcttgctggaccagaacatcctggagctgtacttcaacgacggcgacgtcgtgtccaccaacacctacttcatgaccaccgggaacgcc

ggcagcagcagctcggatagtatcgacacactctggacgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaggatcgta gagctcactagtatcgatttcgaagacagggtggttggctggatggggaaacgctggtcgcgggattcgatcctgctgcttatatcctccctggaagcacacccacgactctgaagaagaaaacgtgcacacacacaacccaaccggccgaatatttgcttccttatcccgggtccaagagagactgcgatgcccccctcaatcagcatcctcctccctgccgcttcaatcttccctgcttgcctgcgcccgcggtgcgccgtctgcccgcccagtcagtcactcctgcacaggccccttgtgcgcagtgctcctgtaccctttaccgctccttccattctgcgaggccccctattgaatgtattcgttgcctgtgtggccaagcgggctgctgggcgcgccgccgtcgggcagtgctcggcgactttggcggaagccgattgttcttctgtaagccacgcgcttgctgctttgggaagagaagggggggggtactgaatggatgaggaggagaaggaggggtattggtattatctgagttgggtgaa gagc

To introduce the Cuphea wrightii ACP-thioesterase 2 (CwTE2) gene(Accession No: U56104) into at the FATA1 locus of strain A, a constructwas generated to express the protein coding region of the CwTE2 geneunder the control of the Prototheca moriformis Amt03 promoter/5′UTR (SEQID NO: 89) and C. vulgaris nitrate reductase 3′UTR. The construct thathas been expressed in strain A can be written asFATA1-CrbTub_yInv_nr::amt03_CwTE2_nr-FATA1 (SEQ ID NO: 254).

Relevant restriction sites in the constructFATA1-CrbTub_yInv_nr::amt03_CwTE2_nr-FATA1 are indicated in lowercase,bold and underlining and are 5′-3′ BspQ 1, Kpn I, Asc I, Mfe I, BamH I,EcoR I, Spe I, Asc I, Pac I, Sac I, BspQ I, respectively. BspQI sitesdelimit the 5′ and 3′ ends of the transforming DNA. Bold, lowercasesequences represent genomic DNA from strain A that permit targetedintegration at FATA1 locus via homologous recombination. Proceeding inthe 5′ to 3′ direction, the C. reinhardtii β-tubulin promoter drivingthe expression of the yeast sucrose invertase gene (conferring theability of strain A to metabolize sucrose) is indicated by boxed text.The initiator ATG and terminator TGA for invertase are indicated byuppercase, bold italics while the coding region is indicated inlowercase italics. The Chlorella vulgaris nitrate reductase 3′ UTR isindicated by lowercase underlined text followed by an endogenous Amt03promoter of Prototheca moriformis, indicated by boxed italics text. TheInitiator ATG and terminator TGA codons of the C. wrightiiACP-thioesterase are indicated by uppercase, bold italics, while theremainder of the ACP-thioesterase coding region is indicated by bolditalics. The C. vulgaris nitrate reductase 3′ UTR is again indicated bylowercase underlined text followed by the strain A FATA1 genomic regionindicated by bold, lowercase text:

gctcttcggagtcactgtgccactgagttcgactggtagctgaatggagtcgctgctccactaaacgaattgtcagcaccgccagccggccgaggacccgagtcatagcgagggtagtagcgcgccatggcaccgaccagcctgcttgccagtactggcgtctcttccgcttctctgtggtcctctgcgcgctccagcgcgtgcgcttttccggtggatcatgcggtccgtggcgcaccgcagcggccgctgcccatgcagcgccgctgcttccgaacagtggcggtcagggccgcacccgcggtagccgtccgtccggaacccgcccaagagttttgggagcagcttgagccctgcaagatggcggaggacaagcgcatcttcctggaggagcaccggtgcgtggaggtccggggctgaccggccgtcgcattcaacgtaatcaatcgcatgatgatcagaggacacgaagtcttggtggcggtggccagaaacactgtccattgcaagggcatagggatgcgttccttcacctctcatttctcatttctgaatccctccctgctcactctttctcctcctccttc

ctgctgcaggccttcctgttcctgctggccggcttcgccgccaagatcagcgcctccatgacgaacgagacgtccgaccgccccctggtgcacttcacccccaacaagggctggatgaacgaccccaacggcctgtggtacgacgagaaggacgccaagtggcacctgtacttccagtacaacccgaacgacaccgtctgggggacgcccttgttctggggccacgccacgtccgacgacctgaccaactgggaggaccagcccatcgccatcgccccgaagcgcaacgactccggcgccttctccggctccatggtggtggactacaacaacacctccggcttcttcaacgacaccatcgacccgcgccagcgctgcgtggccatctggacctacaacaccccggagtccgaggagcagtacatctcctacagcctggacggcggctacaccttcaccgagtaccagaagaaccccgtgctggccgccaactccacccagttccgcgacccgaaggtcttctggtacgagccctcccagaagtggatcatgaccgcggccaagtcccaggactacaagatcgagatctactcctccgacgacctgaagtcctggaagctggagtccgcgttcgccaacgagggcttcctcggctaccagtacgagtgccccggcctgatcgaggtccccaccgagcaggaccccagcaagtcctactgggtgatgttcatctccatcaaccccggcgccccggccggcggctccttcaaccagtacttcgtcggcagcttcaacggcacccacttcgaggccttcgacaaccagtcccgcgtggtggacttcggcaaggactactacgccctgcagaccttcttcaacaccgacccgacctacgggagcgccctgggcatcgcgtgggcctccaactgggagtactccgccttcgtgcccaccaacccctggcgctcctccatgtccctcgtgcgcaagttctccctcaacaccgagtaccaggccaacccggagacggagctgatcaacctgaaggccgagccgatcctgaacatcagcaacgccggcccctggagccggttcgccaccaacaccacgttgacgaaggccaacagctacaacgtcgacctgtccaacagcaccggcaccctggagttcgagctggtgtacgccgtcaacaccacccagacgatctccaagtccgtgttcgcggacctctccctctggttcaagggcctggaggaccccgaggagtacctccgcatgggcttcgaggtgtccgcgtcctccttcttcctggaccgcgggaacagcaaggtgaagttcgtgaaggagaacccctacttcaccaaccgcatgagcgtgaacaaccagcccttcaagagcgagaacgacctgtcctactacaaggtgtacggcttgctggaccagaacatcctggagctgtacttcaacgacggcgacgtcgtgtccaccaacacctacttcatgaccaccgggaacgcc

ggcagcagcagctcggatagtatcgacacactctggacgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaggatcccgcgtctcgaacagagcgcgcagaggaacgctgaagggtctcgcctctgtcgcacctcagcgcggcatacaccacaataaccacctgacgaatgcgcttggttcttcgtccattagcgaagcgtccggttcacacacgtgccacgttggcgaggtggcaggtgacaatgatcggtggagctgatggtcgaaacgttcacagcctagggatatcgaattc

cgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaaagctt gagctcttgttttccagaaggagttgctccttgagcctttcattctcagcctcgataacctccaaagccgctctaattgtggagggggttcgaagacagggtggttggctggatggggaaacgctggtcgcgggattcgatcctgctgcttatatcctccctggaagcacacccacgactctgaagaagaaaacgtgcacacacacaacccaaccggccgaatatttgcttccttatcccgggtccaagagagactgcgatgcccccctcaatcagcatcctcctccctgccgcttcaatcttccctgcttgcctgcgcccgcggtgcgccgtctgcccgcccagtcagtcactcctgcacaggccccttgtgcgcagtgctcctgtaccctttaccgctccttccattctgcgaggccccctattgaatgtattcgttgcctgtgtggccaagcgggctgctgggcgcgccgccgtcgggcagtgctcggcgactttggcggaagccgattgttcttctgtaagccacgcgcttgctgattgggaagagaagggggggggtactgaatggatgaggaggagaaggaggggtattggtattatctgagttgggt gaagagc

Upon individual transformation of plasmid construct 1 or 2 into strainA, positive clones were selected on agar plates comprising sucrose asthe sole carbon source. As in the previous examples, primarytransformants were clonally purified and grown under standard lipidproduction conditions at pH 7 and lipid samples were prepared from driedbiomass from each transformant. Fatty acid profiles were determinedusing direct transesterification methods as described in Example 11. Theresulting fatty acid profiles (expressed as Area % of total fatty acids)from a set of representative clones arising from transformations withconstruct 1 as compared to those of untransformed strain A controls arepresented in Table 66. The resulting fatty acid profiles (expressed asArea % of total fatty acids) from a set of representative clones arisingfrom transformations with construct 2 as compared to those ofuntransformed strain A controls are presented in Table 67.

TABLE 66 Fatty acid profiles of Prototheca moriformis cells comprising aselectable marker to disrupt an endogenous FATA1 allele. %Transformation % C14:0 % C16:0 % C18:0 % C18:1 C18:2 Wildtype 1.23 25.682.83 60.54 7.52 Transformant 1 0.86 16.95 1.75 68.44 9.78 Transformant 20.85 17.33 1.71 68.57 9.31 Transformant 3 0.82 17.40 1.78 68.55 9.22Transformant 4 0.84 17.43 1.78 68.25 9.53 Transformant 5 0.75 17.64 2.0269.02 8.61

Results presented in Table 66 show that ablation of the host'sendogenous FATA1 allele alters the fatty acid profile of the engineeredmicroalgae. The impact of targeting a selectable marker to theendogenous FATA1 allele on the fatty acid profile of the transformedmicrobe is a clear diminution of C16:0 fatty acids with concomitantincrease in C18:1 fatty acids.

TABLE 67 Fatty acid profiles of Prototheca moriformis cells containing aselectable marker and an exogenous thioesterase to disrupt an endogenousFATA1 allele. Carbon % % % % % % % Transformant source C10:0 C12:0 C14:0C16:0 C18:0 C18:1 C18:2 strain A Wildtype Glucose 0.01 0.04 1.38 28.833.00 56.05 8.21 Wildtype Glucose 0.01 0.04 1.50 29.38 3.00 55.29 8.23Wildtype Glucose/Fruc- 0.01 0.05 1.48 28.58 3.20 57.14 7.27 toseWildtype Glucose/Fruc- 0.01 0.04 1.54 29.05 3.23 56.47 7.32 tose >2 1Glucose/Fruc- 4.29 19.98 9.17 20.68 3.47 34.38 6.37 copies tose 2Glucose/Fruc- 3.11 16.17 9.91 15.97 1.57 45.72 5.81 tose 3 Sucrose 4.8424.22 11.56 19.48 2.67 29.56 6.02 4 Sucrose 3.24 16.67 10.39 16.34 1.4344.41 6.00 1-2 1 Glucose/Fruc- 0.18 1.64 1.85 14.43 2.12 70.30 7.63copies tose 2 Glucose/Fruc- 0.18 1.56 1.74 13.56 2.25 71.04 7.72 tose 3Sucrose 0.19 1.69 1.89 13.79 3.15 69.97 7.68 4 Sucrose 0.15 1.26 1.4913.44 2.73 71.46 7.77

Concordant with targeting a selectable marker alone to the host's FATA1allele, integration of a selectable marker concomitant with an exogenousthioesterase results in an alteration of the fatty acid profile of theengineered microalgae. As shown in Table 67 above, targeting anexogenous thioesterase gene to interrupt the FATA1 allele results in aclear diminution of C16:0 fatty acid production. The expression of theCwTE2 thioesterase at the FATA1 locus also impacts mid chain fatty acidsand C18:1 fatty acid production to an extent that is dependent upon thelevel of exogenous thioesterase activity present in the transformantsanalyzed. There is good concordance between copy number of the amplifiedtransgene at the target integration site and thioesterase levels asrevealed either by impacts on fatty acid profiles or recombinant proteinaccumulation as assessed by Western blotting.

Transgenic lines in which the CwTE2 gene has undergone amplificationshow a marked increase in C10:0-C14:0 fatty acids and a concurrentdecrease in C18:1 fatty acids. In contrast, those transformants in whichCwTE2 has undergone little or no amplification are consistent with lowerexpression of the exogenous thioesterase, resulting in a slight increasein mid chain fatty acids and a far greater impact on the increase ofC18:1 fatty acids.

Collectively, these data show that targeted disruption of the host'sendogenous FATA1 allele alters the lipid profile of the engineeredmicroalgae. These data demonstrate the utility and effectiveness ofpolynucleotides permitting targeted disruption of a FATA allele to alterthe fatty acid profile of engineered microbial cells, in particular indecreasing the concentration of C16 fatty acids and increasing theconcentration of C18:1 fatty acids. These data additionally demonstratethe utility and effectiveness of polynucleotides permitting targeteddisruption of a FATA allele while concomitantly expressing an exogenousthioesterase to alter the fatty acid profile of engineered microbialcells, in particular in decreasing the concentration of C16 fatty acids.

B. Altering Lipid Profiles by Knockdown of an Endogenous ProtothecaMoriformis Thioesterase Gene

A construct to down-regulate the Prototheca moriformis FATA1 geneexpression by RNAi was introduced into a Prototheca moriformis UTEX 1435strain A genetic background. The Saccharomyces cerevisiae suc2 sucroseinvertase gene was utilized as a selectable marker, conferring theability to grow on sucrose as a sole-carbon source. The constructutilized the first exon of the FatA1 coding region, followed by theendogenous intron, and a repeat unit of the first exon in the reverseorientation. 5′ and 3′ homologous recombination targeting sequences(flanking the construct) to the 6S genomic region, listed as SEQ ID NO:82 and 84 respectively, were included for integration of the hairpinconstruct into the nuclear genome. This construct is designated6S::β-Tub:suc2:nr::β-tub:hairpinFatA:nr::6S.

Relevant restriction sites in 6S::β-Tub:suc2:nr::β-tub:hairpinFatA:nr::6S are indicated in lowercase, bold and underlining and are5′-3′ BspQ 1, Kpn I, Mfe I, BamH I, EcoR I, Spe I, Xho I, Sac I, BspQ I,respectively. BspQI sites delimit the 5′ and 3′ ends of the transformingDNA. Bold, lowercase sequences represent genomic DNA from strain A thatpermit targeted integration at 6s locus via homologous recombination.Proceeding in the 5′ to 3′ direction, the C. reinhardtii β-tubulinpromoter driving the expression of the yeast sucrose invertase gene(conferring the ability of strain A to metabolize sucrose) is indicatedby boxed text. The initiator ATG and terminator TGA for invertase areindicated by uppercase, bold italics while the coding region isindicated in lowercase italics. The Chlorella vulgaris nitrate reductase3′ UTR is indicated by lowercase underlined text followed by the secondC. reinhardtii β-tubulin promoter driving the expression of the HairpinFatA1, indicated by boxed italics text. The Initiator ATG codon of theFatA1 is indicated by uppercase, bold italics, while the remainder ofthe first exon of FatA1 coding region is indicated by uppercase. Theintron of the FatA gene is indicated as underlined uppercase, and alinker region shown in underlined uppercase, bold italics was created atthe FatA1 intron/reversed first exon junction to aid in RNA splicing inthese vectors. The inverted first exon of FatA1 is indicated byuppercase. The C. vulgaris nitrate reductase 3′ UTR is again indicatedby lowercase underlined text followed by the strain A 6S genomic regionindicated by bold, lowercase text. The sequence of the FATA portions ofthis RNAi construct is listed as SEQ ID NO: 255.

gctcttcgccgccgccactcctgctcgagcgcgcccgcgcgtgcgccgccagcgccttggccttttcgccgcgctcgtgcgcgtcgctgatgtccatcaccaggtccatgaggtctgccttgcgccggctgagccactgcttcgtccgggcggccaagaggagcatgagggaggactcctggtccagggtcctgacgtggtcgcggctctgggagcgggccagcatcatctggctctgccgcaccgaggccgcctccaactggtcctccagcagccgcagtcgccgccgaccctggcagaggaagacaggtgaggggggtatgaattgtacagaacaaccacgagccttgtctaggcagaatccctaccagtcatggctttacctggatgacggcctgcgaacagctgtccagcgaccctcgctgccgccgcttctcccgcacgcttctttccagcaccgtgatggcgcgagccagcgccgcacgctggcgctgcgcttcgccgatctgaggacagtcggggaactctgatcagtctaaacccccttgcgcgttagtgttgccatcctttgcagaccggtgagagccgacttgttgtgcgccaccccccacaccacctcctcccagaccaattctgtcacctttttggcgaaggcatcggcctcggcc

cgcctccatgacgaacgagacgtccgaccgccccctggtgcacttcacccccaacaagggctggatgaacgaccccaacggcctgtggtacgacgagaaggacgccaagtggcacctgtacttccagtacaacccgaacgacaccgtctgggggacgcccttgttctggggccacgccacgtccgacgacctgaccaactgggaggaccagcccatcgccatcgccccgaagcgcaacgactccggcgccttctccggctccatggtggtggactacaacaacacctccggcttcttcaacgacaccatcgacccgcgccagcgctgcgtggccatctggacctacaacaccccggagtccgaggagcagtacatctcctacagcctggacggcggctacaccttcaccgagtaccagaagaaccccgtgctggccgccaactccacccagttccgcgacccgaaggtcttctggtacgagccctcccagaagtggatcatgaccgcggccaagtcccaggactacaagatcgagatctactcctccgacgacctgaagtcctggaagctggagtccgcgttcgccaacgagggcttcctcggctaccagtacgagtgccccggcctgatcgaggtccccaccgagcaggaccccagcaagtcctactgggtgatgttcatctccatcaaccccggcgccccggccggcggctccttcaaccagtacttcgtcggcagcttcaacggcacccacttcgaggccttcgacaaccagtcccgcgtggtggacttcggcaaggactactacgccctgcagaccttcttcaacaccgacccgacctacgggagcgccctgggcatcgcgtgggcctccaactgggagtactccgccttcgtgcccaccaacccctggcgctcctccatgtccctcgtgcgcaagttctccctcaacaccgagtaccaggccaacccggagacggagctgatcaacctgaaggccgagccgatcctgaacatcagcaacgccggcccctggagccggttcgccaccaacaccacgttgacgaaggccaacagctacaacgtcgacctgtccaacagcaccggcaccctggagttcgagctggtgtacgccgtcaacaccacccagacgatctccaagtccgtgttcgcggacctctccctctggttcaagggcctggaggaccccgaggagtacctccgcatgggcttcgaggtgtccgcgtcctccttcttcctggaccgcgggaacagcaaggtgaagttcgtgaaggagaacccctacttcaccaaccgcatgagcgtgaacaaccagcccttcaagagcgagaacgacctgtcctactacaaggtgtacggcttgctggaccagaacatcctggagctgtacttcaacgacggcgacgtcgtgtccaccaacacctacttcatgaccaccgggaacgccctgggctccgtgaacatgacgacgggggtggacaacctgttctacatcgac

ggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgcttttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaggatcccgcgtctcgaacagagcgcgcagaggaacgctgaaggtctcgcctctgtcgcacctcagcgcggcatacaccacaataaccacctgacgaatgcgcttggttcttcgtccattagcgaagcgtccggttcacacacgtgccacgttggcgaggtggcaggtgacaatgatcggtggagctgatg

GTGGTCCTCTGCGCGCTCCAGCGCGTGCGCTTTTCCGGTGGATCATGCGGTCCGTGGCGCACCGCAGCGGCCGCTGCCCATGCAGCGCCGCTGCTTCCGAACAGTGGCGGTCAGGGCCGCACCCGCGGTAGCCGTCCGTCCGGAACCCGCCCAAGAGTTTTGGGAGCAGCTTGAGCCCTGCAAGATGGCGGAGGACAAGCGCATCTTCCTGGAGGAGCACCGGTGCGTGGAGGTCCGGGGCTGACCGGCCGTCGCATTCAACGTAATCAATCGCATGATGATCAGAGGACACGAAGTCTTGGTGGCGGTGGCCAGAAACACTGTCCATTGCAAGGGCATAGGGATGCGTTCCTTCACCTCTCATTTCTCATTTCTGAATCC

CTCAAGCTGCTCCCAAAACTCTTGGGCGGGTTCCGGACGGACGGCTACCGCGGGTGCGGCCCTGACCGCCACTGTTCGGAAGCAGCGGCGCTGCATGGGCAGCGGCCGCTGCGGTGCGCCACGGACCGCATGATCCACCGGAAAAGCGCACGCGCTGGAGCGCGCAGAGGACCACAGAGAAGCGGAAGAGACGCCAGTACTGGCAAGCAGGCTGGT CGGTGCCAT atcgatagatctcttaaggcagcagcagctcggatagtatcgacacactctggacgctggtcgtgtgatggactgttgccgccacacttgctgccttgacctgtgaatatccctgccgcttttatcaaacagcctcagtgtgtttgatcttgtgtgtacgcgctttgcgagttgctagctgcttgtgctatttgcgaataccacccccagcatccccttccctcgtttcatatcgcttgcatcccaaccgcaacttatctacgctgtcctgctatccctcagcgctgctcctgctcctgctcactgcccctcgcacagccttggtttgggctccgcctgtattctcctggtactgcaacctgtaaaccagcactgcaatgctgatgcacgggaagtagtgggatgggaacacaaatggaaagcttaattaagagctc ttgttttccagaaggagttgctccttgagcctttcattctcagcctcgataacctccaaagccgctctaattgtggagggggttcgaatttaaaagcttggaatgttggttcgtgcgtctggaacaagcccagacttgttgctcactgggaaaaggaccatcagctccaaaaaacttgccgctcaaaccgcgtacctctgctttcgcgcaatctgccctgttgaaatcgccaccacattcatattgtgacgcttgagcagtctgtaattgcctcagaatgtggaatcatctgccccctgtgcgagcccatgccaggcatgtcgcgggcgaggacacccgccactcgtacagcagaccattatgctacctcacaatagttcataacagtgaccatatttctcgaagctccccaacgagcacctccatgctctgagtggccaccccccggccctggtgcttgcggagggcaggtcaaccggcatggggctaccgaaatccccgaccggatcccaccacccccgcgatgggaagaatctctccccgggatgtgggcccaccaccagcacaacctgctggcccaggcgagcgtcaaaccataccacacaaatatccttggcatcggccctgaattccttctgccgctctgctacccggtgcttctgtccgaagcaggggttgctagggatcgctccgagtccgcaaacccttgtcgcgtggcggggcttgttcgagctt gaagagcExpression of 6S::β-Tub:suc2:nr::β-tub:hairpin FatA:nr::6S leads to theformation of a hairpin RNA to silence the target FatA gene product. Upontransformation of the construct 6S::β-Tub:suc2:nr::β-tub:hairpinFatA:nr::6S into strain A, positive clones were selected on agar platescomprising sucrose as the sole carbon source. Primary transformants wereclonally purified and grown under standard lipid production conditionsat pH 5.0 and lipid samples were prepared from dried biomass from eachtransformant. Fatty acid profiles were determined using directtransesterification methods as described in Example 11. The resultingfatty acid profiles (expressed as Area % of total fatty acids) from aset of representative clones arising from transformations as compared tothose of an untransformed strain A control are presented in Table 68.

TABLE 68 Fatty acid profiles of Prototheca moriformis cells containingan RNA hairpin construct to down-regulate the expression of FATA. % % %% % % % % Transformant C10:0 C12:0 C14:0 C16:0 C16:1 C18:0 C18:1 C18:2Untransformed 0.01 0.03 1.23 25.68 0.96 2.83 60.54 7.52 Transformant0.01 0.03 0.71 15.10 1.05 1.67 72.08 8.27 1 Transformant 0.01 0.03 0.8115.66 1.16 1.56 70.03 9.61 2 Transformant 0.01 0.03 1.09 22.67 1.05 2.1263.18 8.66 3 Transformant 0.01 0.04 1.14 23.31 1.01 2.23 62.83 8.26 4

The data presented in Table 68 show a clear impact of the expression ofa FATA hairpin RNA construct on the C16 and C18:1 fatty acid profile ofthe host organism. The fatty acid profiles of strain A transformantscomprising the FATA hairpin RNA construct demonstrated an increase inthe percentage of C18:1 fatty acids with a concomitant diminution of C16fatty acids. These data illustrate the successful expression and use ofa polynucleotide FATA RNA hairpin construct in Prototheca moriformis toalter the fatty acid profile of engineered host microbes, and inparticular in increasing the concentration of C18:1 fatty acids anddecreasing C16 fatty acids in microbial cells.

Example 21: Engineering Chlorella sorokinian

Expression of recombinant genes in accordance with the present inventionin Chlorella sorokinian can be accomplished by modifying the methods andvectors taught by Dawson et al. as discussed herein. Briefly, Dawson etal., Current Microbiology Vol. 35 (1997) pp. 356-362, reported thestable nuclear transformation of Chlorella sorokiniana with plasmid DNA.Using the transformation method of microprojectile bombardment, Dawsonintroduced the plasmid pSV72-NRg, encoding the full Chlorella vulgarisnitrate reductase gene (NR, GenBank Accession No. U39931), into mutantChlorella sorokiniana (NR-mutants). The NR-mutants are incapable ofgrowth without the use of nitrate as a source of nitrogen. Nitratereductase catalyzes the conversion of nitrate to nitrite. Prior totransformation, Chlorella sorokiniana NR-mutants were unable to growbeyond the microcolony stage on culture medium comprising nitrate (NO₃⁻) as the sole nitrogen source. The expression of the Chlorella vulgarisNR gene product in NR-mutant Chlorella sorokiniana was used as aselectable marker to rescue the nitrate metabolism deficiency. Upontransformation with the pSV72-NRg plasmid, NR-mutant Chlorellasorokiniana stably expressing the Chlorella vulgaris NR gene productwere obtained that were able to grow beyond the microcolony stage onagar plates comprising nitrate as the sole carbon source. Evaluation ofthe DNA of the stable transformants was performed by Southern analysisand evaluation of the RNA of the stable transformants was performed byRNase protection. Selection and maintenance of the transformed Chlorellasorokiniana (NR mutant) was performed on agar plates (pH 7.4) comprising0.2 g/L MgSO₄, 0.67 g/L KH₂PO₄, 3.5 g/L K₂HPO₄, 1.0 g/L Na₃C₆H₅O₇.H₂Oand 16.0 g/L agar, an appropriate nitrogen source (e.g., NO₃ ⁻),micronutrients, and a carbon source. Dawson also reported thepropagation of Chlorella sorokiniana and Chlorella sorokiniana NRmutants in liquid culture medium. Dawson reported that the plasmidpSV72-NRg and the promoter and 3′ UTR/terminator of the Chlorellavulgaris nitrate reductase gene were suitable to enable heterologousgene expression in Chlorella sorokiniana NR-mutants. Dawson alsoreported that expression of the Chlorella vulgaris nitrate reductasegene product was suitable for use as a selectable marker in Chlorellasorokiniana NR-mutants.

In an embodiment of the present invention, vector pSV72-NRg, comprisingnucleotide sequence encoding the Chlorella vulgaris nitrate reductase(CvNR) gene product for use as a selectable marker, is constructed andmodified to further comprise a lipid biosynthesis pathway expressioncassette sequence, thereby creating a transformation vector. The lipidbiosynthesis pathway expression cassette encodes one or more lipidbiosynthesis pathway proteins selected from Table 70, eachprotein-coding sequence codon-optimized for expression in Chlorellasorokiniana to reflect the codon bias inherent in nuclear genes ofChlorella sorokiniana in accordance with Tables 69A-D. For each lipidbiosynthesis pathway protein of Table 70, the codon-optimized genesequence can individually be operably linked to the CvNR promoterupstream of the protein-coding sequence and operably linked to the CvNR3′UTR/terminator at the 3′ region, or downstream, of the protein-codingsequence. The transformation construct may additionally comprisehomology regions to the Chlorella sorokiniana genome for targetedgenomic integration of the transformation vector. Homology regions maybe selected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Chlorellasorokiniana with the transformation vector is achieved throughwell-known transformation techniques including microprojectilebombardment or other known methods. Activity of the CvNR gene productcan be used as a selectable marker to rescue the nitrogen assimilationdeficiency of Chlorella sorokiniana NR mutant strains and to select forChlorella sorokiniana NR-mutants stably expressing the transformationvector. Growth media suitable for Chlorella sorokiniana lipid productioninclude, but are not limited to 0.5 g/L KH₂PO₄, 0.5 g/L K₂HPO₄, 0.25 g/LMgSO₄-7H₂O, with supplemental micronutrients and the appropriatenitrogen and carbon sources (Patterson, Lipids Vol. 5:7 (1970), pp.597-600). Evaluation of fatty acid profiles of Chlorella sorokinianalipids can be assessed through standard lipid extraction and analyticalmethods described herein.

Examples 22-44: Introduction and Tables

Examples 22-44 below describe the engineering of various microorganismsin accordance with the present invention. To alter the fatty acidprofile of a microorganism, microorganisms can be genetically modifiedwherein endogenous or exogenous lipid biosynthesis pathway enzymes areexpressed, overexpressed, or attenuated. Steps to genetically engineer amicrobe to alter its fatty acid profile as to the degree of fatty acidunsaturation and to decrease or increase fatty acid chain lengthcomprise the design and construction of a transformation vector (e.g., aplasmid), transformation of the microbe with one or more vectors,selection of transformed microbes (transformants), growth of thetransformed microbe, and analysis of the fatty acid profile of thelipids produced by the engineered microbe.

Transgenes that alter the fatty acid profiles of host organisms can beexpressed in numerous eukaryotic microbes. Examples of expression oftransgenes in eukaryotic microbes including Chlamydomonas reinhardtii,Chlorella ellipsoidea, Chlorella saccarophila, Chlorella vulgaris,Chlorella kessleri, Chlorella sorokiniana, Haematococcus pluvialis,Gonium pectorale, Volvox carteri, Dunaliella tertiolecta, Dunaliellaviridis, Dunaliella salina, Closterium peracerosum-strigosum-littoralecomplex, Nannochloropsis sp., Thalassiosira pseudonana, Phaeodactylumtricornutum, Navicula saprophila, Cylindrotheca fusiformis, Cyclotellacryptica, Symbiodinium microadriacticum, Amphidinium sp., Chaetocerossp., Mortierella alpina, and Yarrowia lipolytica can be found in thescientific literature. These expression techniques can be combined withthe teachings of the present invention to produce engineeredmicroorganisms with altered fatty acid profiles.

Transgenes that alter the fatty acid profiles of host organisms can alsobe expressed in numerous prokaryotic microbes. Examples of expression oftransgenes in oleaginous microbes including Rhodococcus opacus can befound in the literature. These expression techniques can be combinedwith the teachings of the present invention to produce engineeredmicroorganisms with altered fatty acid profiles.

TABLEs 69A-D Codon preference listing. Amino Chlorella ChlorellaChlorella Chlorella Dunaliella Volvox Haematococcus Acid Codonsorokiniana vulgaris ellipsoidea kessleri tertiolecta carteri pluvialisAla GCG 0.20 0.25 0.15 0.14 0.09 0.25 0.21 Ala GCA 0.05 0.24 0.32 0.100.17 0.13 0.27 Ala GCT 0.12 0.16 0.26 0.18 0.31 0.26 0.17 Ala GCC 0.630.35 0.27 0.58 0.43 0.36 0.35 Arg AGG 0.03 0.09 0.10 0.09 0.26 0.08 0.14Arg AGA 0.04 0.05 0.14 0.01 0.09 0.03 0.05 Arg CGG 0.06 0.19 0.09 0.060.06 0.17 0.15 Arg CGA 0.00 0.10 0.08 0.00 0.08 0.08 0.10 Arg CGT 0.060.09 0.37 0.14 0.12 0.22 0.13 Arg CGC 0.81 0.48 0.22 0.71 0.40 0.43 0.42Asn AAT 0.04 0.16 0.43 0.06 0.27 0.23 0.21 Asn AAC 0.96 0.84 0.57 0.940.73 0.77 0.79 Asp GAT 0.13 0.25 0.47 0.12 0.40 0.35 0.27 Asp GAC 0.870.75 0.53 0.88 0.60 0.65 0.73 Cys TGT 0.06 0.13 0.43 0.09 0.20 0.17 0.27Cys TGC 0.94 0.87 0.57 0.91 0.80 0.83 0.64 End TGA 0.00 0.72 0.14 0.140.36 0.24 0.70 End TAG 0.33 0.11 0.29 0.00 0.00 0.18 0.22 End TAA 0.670.17 4.00 0.86 0.64 0.59 0.09 Gln CAG 0.42 0.40 0.15 0.40 0.27 0.29 0.33Gln CAA 0.04 0.04 0.21 0.40 0.27 0.07 0.10 Glu GAG 0.53 0.50 0.33 0.400.27 0.53 0.49 Glu GAA 0.02 0.06 0.31 0.40 0.27 0.11 0.07 Gly GGG 0.040.16 0.19 0.08 0.10 0.12 0.22 Gly GGA 0.02 0.11 0.13 0.07 0.13 0.12 0.11Gly GGT 0.03 0.12 0.39 0.24 0.25 0.23 0.15 Gly GGC 0.91 0.61 0.29 0.960.51 0.53 0.52 His CAT 0.14 0.16 0.30 0.08 0.25 0.35 0.27 His CAC 0.860.84 0.70 0.93 0.75 0.65 0.73 Ile ATA 0.00 0.04 0.07 0.01 0.04 0.08 0.09Ile ATT 0.15 0.30 0.63 0.29 0.31 0.35 0.29 Ile ATC 0.85 0.66 0.65 0.690.65 0.57 0.62 Leu TTG 0.03 0.07 0.03 0.05 0.14 0.14 0.16 Leu TTA 0.000.01 0.32 0.00 0.02 0.03 0.02 Leu CTG 0.72 0.61 0.34 0.61 0.60 0.45 0.53Leu CTA 0.01 0.03 0.03 0.04 0.04 0.07 0.07 Leu CTT 0.04 0.08 0.16 0.060.06 0.14 0.09 Leu CTC 0.20 0.20 0.12 0.24 0.14 0.17 0.13 Lys AAG 0.980.94 0.54 0.98 0.90 0.90 0.84 Lys AAA 0.02 0.06 0.46 0.02 0.10 0.10 0.16Met ATG 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Phe TTT 0.28 0.32 0.42 0.310.24 0.27 0.35 Phe TTC 0.72 0.68 0.58 0.69 0.76 0.73 0.65 Pro CCG 0.180.31 0.09 0.07 0.04 0.34 0.15 Pro CCA 0.06 0.17 0.36 0.07 0.04 0.20 0.24Pro CCT 0.10 0.14 0.25 0.17 0.04 0.19 0.29 Pro CCC 0.66 0.38 0.29 0.690.04 0.27 0.32 Ser AGT 0.03 0.04 0.14 0.02 0.08 0.08 0.07 Ser AGC 0.270.38 0.18 0.18 0.31 0.27 0.31 Ser TCG 0.12 0.14 0.08 0.10 0.02 0.19 0.10Ser TCA 0.03 0.08 0.14 0.08 0.09 0.09 0.14 Ser TCT 0.09 0.11 0.26 0.180.19 0.14 0.13 Ser TCC 0.47 0.24 0.20 0.44 0.30 0.24 0.24 Thr ACG 0.110.20 0.13 0.05 0.12 0.27 0.19 Thr ACA 0.01 0.20 0.32 0.07 0.20 0.12 0.23Thr ACT 0.12 0.13 0.29 0.12 0.24 0.20 0.18 Thr ACC 0.76 0.47 0.26 0.760.44 0.41 0.40 Trp TGG 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Tyr TAT 0.070.15 0.43 0.27 0.28 0.24 0.19 Tyr TAC 0.93 0.85 0.57 0.73 0.72 0.76 0.81Val GTG 0.71 0.54 0.37 0.60 0.54 0.46 0.62 Val GTA 0.00 0.05 0.25 0.030.09 0.07 0.09 Val GTT 0.11 0.14 0.24 0.09 0.14 0.17 0.09 Val GTC 0.180.27 0.14 0.28 0.23 0.30 0.21 Closterium peracerosum- strigosum-Dunaliella Dunaliella Gonium Phaeodactylum Chaetoceros Amino Acid Codonlittorale complex viridis salina pectorale tricornutum compressum AlaGCG 0.48 0.13 0.15 0.43 0.15 0.08 Ala GCA 0.10 0.27 0.20 0.09 0.10 0.37Ala GCT 0.15 0.25 0.27 0.08 0.23 0.36 Ala GCC 0.26 0.35 0.39 0.41 0.520.18 Arg AGG 0.04 0.25 0.22 0.13 0.02 0.14 Arg AGA 0.00 0.06 0.05 0.000.04 0.29 Arg CGG 0.18 0.08 0.12 0.40 0.10 0.00 Arg CGA 0.00 0.06 0.060.05 0.12 0.19 Arg CGT 0.13 0.15 0.13 0.08 0.41 0.38 Arg CGC 0.64 0.390.43 0.35 0.31 0.00 Asn AAT 0.04 0.17 0.23 0.07 0.30 0.58 Asn AAC 0.960.83 0.77 0.93 0.65 0.42 Asp GAT 0.30 0.38 0.40 0.11 0.41 0.53 Asp GAC0.70 0.62 0.60 0.89 0.59 0.47 Cys TGT 0.06 0.24 0.17 0.20 0.39 0.44 CysTGC 0.94 0.76 0.83 0.90 0.61 0.56 End TGA 0.75 0.31 0.37 0.50 0.06 0.50End TAG 0.00 0.15 0.14 0.00 0.13 0.00 End TAA 0.25 0.54 0.49 0.50 0.810.50 Gln CAG 0.53 0.36 0.32 0.31 0.23 0.16 Gln CAA 0.09 0.12 0.08 0.070.14 0.19 Glu GAG 0.31 0.44 0.51 0.56 0.21 0.28 Glu GAA 0.06 0.09 0.090.07 0.42 0.37 Gly GGG 0.31 0.14 0.10 0.18 0.08 0.12 Gly GGA 0.06 0.110.12 0.09 0.34 0.33 Gly GGT 0.09 0.22 0.22 0.07 0.30 0.39 Gly GGC 0.530.54 0.56 0.65 0.28 0.16 His CAT 0.33 0.25 0.25 0.43 0.28 0.84 His CAC0.67 0.75 0.75 0.57 0.72 0.16 Ile ATA 0.03 0.03 0.03 0.07 0.03 0.12 IleATT 0.23 0.25 0.31 0.33 0.51 0.65 Ile ATC 0.74 0.72 0.66 0.59 0.46 0.23Leu TTG 0.04 0.11 0.12 0.04 0.26 0.11 Leu TTA 0.00 0.01 0.01 0.00 0.020.14 Leu CTG 0.31 0.60 0.61 0.64 0.15 0.05 Leu CTA 0.01 0.05 0.04 0.010.05 0.08 Leu CTT 0.04 0.07 0.08 0.05 0.18 0.51 Leu CTC 0.60 0.16 0.140.26 0.34 0.11 Lys AAG 0.86 0.87 0.89 0.93 0.75 0.52 Lys AAA 0.14 0.130.11 0.07 0.25 0.48 Met ATG 1.00 1.00 1.00 1.00 1.00 1.00 Phe TTT 0.090.25 0.29 0.10 0.44 0.65 Phe TTC 0.91 0.75 0.71 0.90 0.56 0.35 Pro CCG0.28 0.10 0.08 0.53 0.29 0.05 Pro CCA 0.15 0.10 0.17 0.09 0.12 0.45 ProCCT 0.12 0.10 0.30 0.04 0.20 0.33 Pro CCC 0.44 0.10 0.45 0.34 0.40 0.17Ser AGT 0.04 0.09 0.06 0.02 0.12 0.14 Ser AGC 0.05 0.31 0.32 0.20 0.120.07 Ser TCG 0.22 0.04 0.06 0.42 0.19 0.08 Ser TCA 0.16 0.08 0.10 0.090.06 0.31 Ser TCT 0.05 0.17 0.15 0.07 0.15 0.23 Ser TCC 0.47 0.31 0.300.20 0.35 0.18 Thr ACG 0.30 0.16 0.13 0.42 0.23 0.10 Thr ACA 0.06 0.210.18 0.03 0.13 0.38 Thr ACT 0.22 0.18 0.23 0.08 0.19 0.27 Thr ACC 0.420.46 0.46 0.47 0.45 0.25 Trp TGG 1.00 1.00 1.00 1.00 1.00 1.00 Tyr TAT0.07 0.16 0.21 0.12 0.18 0.67 Tyr TAC 0.93 0.84 0.79 0.88 0.82 0.33 ValGTG 0.50 0.64 0.62 0.57 0.22 0.30 Val GTA 0.02 0.03 0.05 0.04 0.09 0.27Val GTT 0.06 0.11 0.11 0.04 0.22 0.10 Val GTC 0.42 0.22 0.23 0.35 0.470.33 Amino Cylindrotheca Amphidinium Symbiodinium NannochloropsisCyclotella Navicula Thalassiosira C. Acid Codon fusiformis carteraemicroadriacticum sp cryptica pelliculosa pseudonana reinhardtii Ala GCG0.07 0.17 0.22 0.24 0.11 0.00 0.11 0.35 Ala GCA 0.14 0.33 0.26 0.10 0.160.13 0.25 0.08 Ala GCT 0.35 0.29 0.20 0.17 0.45 0.44 0.33 0.13 Ala GCC0.43 0.20 0.32 0.48 0.27 0.44 0.30 0.43 Arg AGG 0.09 0.15 0.27 0.00 0.090.05 0.18 0.05 Arg AGA 0.14 0.03 0.27 0.00 0.05 0.10 0.17 0.01 Arg CGG0.06 0.08 0.09 0.00 0.04 0.05 0.06 0.20 Arg CGA 0.16 0.18 0.09 0.29 0.080.35 0.11 0.04 Arg CGT 0.34 0.18 0.09 0.14 0.47 0.20 0.34 0.09 Arg CGC0.22 0.40 0.18 0.57 0.28 0.25 0.15 0.62 Asn AAT 0.42 0.37 0.21 0.00 0.250.47 0.43 0.09 Asn AAC 0.58 0.63 0.79 1.00 0.75 0.53 0.57 0.91 Asp GAT0.54 0.54 0.50 0.20 0.52 0.20 0.56 0.14 Asp GAC 0.46 0.46 0.50 0.80 0.480.80 0.44 0.86 Cys TGT 0.44 0.75 0.50 0.00 0.29 0.10 0.54 0.10 Cys TGC0.56 0.25 0.50 1.00 0.71 0.90 0.46 0.90 End TGA 0.13 0.50 1.00 0.00 0.100.00 0.31 0.27 End TAG 0.10 0.00 0.00 0.00 0.00 0.00 0.38 0.22 End TAA0.77 0.50 0.00 1.00 0.90 1.00 0.31 0.52 Gln CAG 0.12 0.33 0.28 0.41 0.190.21 0.16 0.38 Gln CAA 0.25 0.15 0.17 0.00 0.17 0.28 0.19 0.04 Glu GAG0.23 0.41 0.50 0.59 0.38 0.17 0.40 0.55 Glu GAA 0.39 0.10 0.06 0.00 0.260.34 0.26 0.03 Gly GGG 0.06 0.19 0.32 0.10 0.10 0.03 0.12 0.11 Gly GGA0.47 0.10 0.12 0.05 0.45 0.28 0.51 0.06 Gly GGT 0.35 0.34 0.16 0.25 0.220.13 0.23 0.11 Gly GGC 0.12 0.37 0.40 0.60 0.24 0.56 0.14 0.72 His CAT0.39 0.12 0.40 0.00 0.42 1.00 0.50 0.11 His CAC 0.61 0.88 0.60 1.00 0.580.00 0.50 0.89 Ile ATA 0.06 0.05 0.00 0.00 0.04 0.00 0.08 0.03 Ile ATT0.42 0.53 0.38 0.14 0.53 0.73 0.38 0.22 Ile ATC 0.52 0.42 0.63 0.86 0.420.27 0.54 0.75 Leu TTG 0.26 0.35 0.39 0.22 0.20 0.16 0.29 0.04 Leu TTA0.09 0.01 0.00 0.00 0.03 0.00 0.05 0.01 Leu CTG 0.09 0.22 0.39 0.09 0.060.12 0.08 0.73 Leu CTA 0.05 0.00 0.04 0.00 0.03 0.04 0.06 0.03 Leu CTT0.37 0.31 0.13 0.04 0.39 0.36 0.20 0.05 Leu CTC 0.13 0.12 0.04 0.65 0.290.32 0.32 0.15 Lys AAG 0.60 0.93 0.85 1.00 0.70 0.83 0.76 0.95 Lys AAA0.40 0.07 0.15 0.00 0.30 0.17 0.24 0.05 Met ATG 1.00 1.00 1.00 1.00 1.001.00 1.00 1.00 Phe TTT 0.37 0.21 0.25 0.20 0.31 0.78 0.38 0.16 Phe TTC0.63 0.79 0.75 0.80 0.69 0.22 0.62 0.84 Pro CCG 0.11 0.14 0.18 0.08 0.100.21 0.16 0.33 Pro CCA 0.33 0.42 0.09 0.08 0.16 0.29 0.31 0.08 Pro CCT0.32 0.22 0.41 0.25 0.35 0.21 0.31 0.13 Pro CCC 0.24 0.22 0.32 0.58 0.390.29 0.23 0.47 Ser AGT 0.12 0.13 0.09 0.00 0.09 0.13 0.18 0.04 Ser AGC0.09 0.24 0.14 0.13 0.08 0.28 0.11 0.35 Ser TCG 0.13 0.03 0.05 0.00 0.150.25 0.17 0.25 Ser TCA 0.12 0.25 0.05 0.00 0.12 0.08 0.12 0.05 Ser TCT0.30 0.16 0.23 0.13 0.39 0.25 0.23 0.07 Ser TCC 0.24 0.19 0.45 0.75 0.180.03 0.19 0.25 Thr ACG 0.09 0.14 0.10 0.28 0.10 0.18 0.21 0.30 Thr ACA0.15 0.28 0.10 0.00 0.15 0.09 0.19 0.08 Thr ACT 0.39 0.12 0.10 0.17 0.330.41 0.28 0.10 Thr ACC 0.37 0.47 0.70 0.56 0.43 0.32 0.32 0.52 Trp TGG1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 Tyr TAT 0.38 0.32 0.20 0.00 0.380.20 0.39 0.10 Tyr TAC 0.62 0.68 0.80 1.00 0.62 0.80 0.61 0.90 Val GTG0.11 0.65 0.67 0.31 0.16 0.18 0.29 0.67 Val GTA 0.06 0.05 0.00 0.00 0.090.09 0.16 0.03 Val GTT 0.38 0.08 0.11 0.15 0.42 0.09 0.28 0.07 Val GTC0.46 0.21 0.22 0.54 0.33 0.64 0.27 0.22 Yarrowia Mortierella RhodococcusAmino Acid Codon lipolytica alpina opacus Ala GCG 0.08 0.14 0.35 Ala GCA0.11 0.12 0.14 Ala GCT 0.35 0.29 0.09 Ala GCC 0.46 0.45 0.43 Arg AGG0.05 0.05 0.05 Arg AGA 0.13 0.06 0.02 Arg CGG 0.12 0.06 0.26 Arg CGA0.52 0.09 0.12 Arg CGT 0.11 0.32 0.11 Arg CGC 0.07 0.42 0.44 Asn AAT0.17 0.15 0.21 Asn AAC 0.83 0.85 0.79 Asp GAT 0.35 0.42 0.24 Asp GAC0.65 0.58 0.76 Cys TGT 0.46 0.13 0.26 Cys TGC 0.54 0.87 0.74 End TGA0.16 0.05 0.72 End TAG 0.38 0.25 0.17 End TAA 0.46 0.70 0.11 Gln CAG0.33 0.36 0.28 Gln CAA 0.08 0.06 0.06 Glu GAG 0.44 0.49 0.45 Glu GAA0.14 0.09 0.22 Gly GGG 0.05 0.03 0.18 Gly GGA 0.28 0.29 0.15 Gly GGT0.32 0.32 0.20 Gly GGC 0.34 0.36 0.48 His CAT 0.34 0.27 0.20 His CAC0.66 0.73 0.80 Ile ATA 0.03 0.01 0.05 Ile ATT 0.44 0.33 0.14 Ile ATC0.53 0.66 0.81 Leu TTG 0.09 0.27 0.09 Leu TTA 0.02 0.00 0.01 Leu CTG0.37 0.26 0.41 Leu CTA 0.05 0.02 0.03 Leu CTT 0.18 0.12 0.06 Leu CTC0.29 0.32 0.40 Lys AAG 0.84 0.91 0.80 Lys AAA 0.16 0.09 0.20 Met ATG1.00 1.00 1.00 Phe TTT 0.38 0.39 0.09 Phe TTC 0.62 0.61 0.91 Pro CCG0.10 0.07 0.52 Pro CCA 0.10 0.08 0.09 Pro CCT 0.32 0.36 0.07 Pro CCC0.47 0.49 0.32 Ser AGT 0.07 0.05 0.08 Ser AGC 0.11 0.14 0.23 Ser TCG0.16 0.32 0.33 Ser TCA 0.08 0.08 0.07 Ser TCT 0.28 0.12 0.05 Ser TCC0.30 0.29 0.24 Thr ACG 0.11 0.17 0.28 Thr ACA 0.14 0.10 0.11 Thr ACT0.26 0.23 0.07 Thr ACC 0.49 0.49 0.53 Trp TGG 1.00 1.00 1.00 Tyr TAT0.18 0.20 0.18 Tyr TAC 0.82 0.80 0.82 Val GTG 0.33 0.22 0.37 Val GTA0.05 0.02 0.05 Val GTT 0.26 0.27 0.10 Val GTC 0.36 0.49 0.49

TABLE 70 Lipid biosynthesis pathway proteins. 3-Ketoacyl ACP synthaseCuphea hookeriana 3-ketoacyl-ACP synthase (GenBank Acc. No. AAC68861.1),Cuphea wrightii beta-ketoacyl-ACP synthase II (GenBank Acc. No.AAB37271.1), Cuphea lanceolata beta-ketoacyl-ACP synthase IV (GenBankAcc. No. CAC59946.1), Cuphea wrightii beta-ketoacyl-ACP synthase II(GenBank Acc. No. AAB37270.1), Ricinus communis ketoacyl-ACP synthase(GenBank Acc. No. XP_002516228), Gossypium hirsutum ketoacyl- ACPsynthase (GenBank Acc. No. ADK23940.1), Glycine max plastid3-keto-acyl-ACP synthase II-A (GenBank Acc No. AAW88763.1), Elaeisguineensis beta-ketoacyl-ACP synthase II (GenBank Acc. No. AAF26738.2),Helianthus annuus plastid 3-keto-acyl-ACP synthase I (GenkBank Acc. No.ABM53471.1), Glycine max3-keto-acyl-ACP synthase I (GenkBank Acc. No.NP_001238610.1), Helianthus annuus plastid 3-keto-acyl-ACP synthase II(GenBank Acc ABI18155.1), Brassica napus beta-ketoacyl-ACP synthetase 2(GenBank Acc. No. AAF61739.1), Perilla frutescens beta-ketoacyl-ACPsynthase II (GenBank Acc. No. AAC04692.1), Helianthus annusbeta-ketoacyl-ACP synthase II (GenBank Accession No. ABI18155), Ricinuscommunis beta-ketoacyl-ACP synthase II (GenBank Accession No. AAA33872),Haematococcus pluvialis beta-ketoacyl acyl carrier protein synthase(GenBank Accession No. HM560033.1), Jatropha curcasbeta ketoacyl-ACPsynthase I (GenBank Accession No. ABJ90468.1), Populus trichocarpabeta-ketoacyl-ACP synthase I (GenBank Accession No. XP_002303661.1),Coriandrum sativum beta-ketoacyl- ACP synthetase I (GenBank AccessionNo. AAK58535.1), Arabidopsis thaliana 3-oxoacyl- [acyl-carrier-protein]synthase I (GenBank Accession No. NP_001190479.1), Vitis vinifera 3-oxoacyl-[acyl-carrier-protein] synthase I (GenBank Accession No.XP_002272874.2) Fatty acyl-ACP Thioesterases Umbellularia californicafatty acyl-ACP thioesterase (GenBank Acc. No. AAC49001), Cinnamomumcamphora fatty acyl-ACP thioesterase (GenBank Acc. No. Q39473),Umbellularia californica fatty acyl-ACP thioesterase (GenBank Acc. No.Q41635), Myristica fragrans fatty acyl-ACP thioesterase (GenBank Acc.No. AAB71729), Myristica fragrans fatty acyl-ACP thioesterase (GenBankAcc. No. AAB71730), Elaeis guineensis fatty acyl- ACP thioesterase(GenBank Acc. No. ABD83939), Elaeis guineensis fatty acyl-ACPthioesterase (GenBank Acc. No. AAD42220), Populus tomentosa fattyacyl-ACP thioesterase (GenBank Acc. No. ABC47311), Arabidopsis thalianafatty acyl-ACP thioesterase (GenBank Acc. No. NP_172327), Arabidopsisthaliana fatty acyl-ACP thioesterase (GenBank Acc. No. CAA85387),Arabidopsis thaliana fatty acyl-ACP thioesterase (GenBank Acc. No.CAA85388), Gossypium hirsutum fatty acyl-ACP thioesterase (GenBank Acc.No. Q9SQI3), Cuphea lanceolata fatty acyl-ACP thioesterase (GenBank Acc.No. CAA54060), Cuphea hookeriana fatty acyl-ACP thioesterase (GenBankAcc. No. AAC72882), Cuphea calophylla subsp. mesostemon fatty acyl-ACPthioesterase (GenBank Acc. No. ABB71581), Cuphea lanceolata fattyacyl-ACP thioesterase (GenBank Acc. No. CAC19933), Elaeis guineensisfatty acyl-ACP thioesterase (GenBank Acc. No. AAL15645), Cupheahookeriana fatty acyl- ACP thioesterase (GenBank Acc. No. Q39513),Gossypium hirsutum fatty acyl-ACP thioesterase (GenBank Acc. No.AAD01982), Vitis vinifera fatty acyl-ACP thioesterase (GenBank Acc. No.CAN81819), Garcinia mangostana fatty acyl-ACP thioesterase (GenBank Acc.No. AAB51525), Brassica juncea fatty acyl-ACP thioesterase (GenBank Acc.No. ABI18986), Madhuca longifolia fatty acyl-ACP thioesterase (GenBankAcc. No. AAX51637), Brassica napus fatty acyl-ACP thioesterase (GenBankAcc. No. ABH11710), Brassica napus fatty acyl-ACP thioesterase (GenBankAcc. No. CAA52070.1), Oryza sativa (indica cultivar-group) fattyacyl-ACP thioesterase (GenBank Acc. No. EAY86877), Oryza sativa(japonica cultivar-group) fatty acyl-ACP thioesterase (GenBank Acc. No.NP_001068400), Oryza sativa (indica cultivar-group) fatty acyl-ACPthioesterase (GenBank Acc. No. EAY99617), Cuphea hookeriana fattyacyl-ACP thioesterase (GenBank Acc. No. AAC49269), Ulmus Americana fattyacyl-ACP thioesterase (GenBank Acc. No. AAB71731), Cuphea lanceolatafatty acyl-ACP thioesterase (GenBank Acc. No. CAB60830), Cupheapalustris fatty acyl-ACP thioesterase (GenBank Acc. No. AAC49180), Irisgermanica fatty acyl-ACP thioesterase (GenBank Acc. No. AAG43858, Irisgermanica fatty acyl-ACP thioesterase (GenBank Acc. No. AAG43858.1),Cuphea palustris fatty acyl-ACP thioesterase (GenBank Acc. No.AAC49179), Myristica fragrans fatty acyl-ACP thioesterase (GenBank Acc.No. AAB71729), Myristica fragrans fatty acyl-ACP thioesterase (GenBankAcc. No. AAB717291.1), Cuphea hookeriana fatty acyl-ACP thioesteraseGenBank Acc. No. U39834), Umbelluaria californica fatty acyl-ACPthioesterase (GenBank Acc. No. M94159), Cinnamomum camphora fattyacyl-ACP thioesterase (GenBank Acc. No. U31813), Ricinus communis fattyacyl-ACP thioesterase (GenBank Acc. No. ABS30422.1), Helianthus annuusacyl-ACP thioesterase (GenBank Accession No. AAL79361.1), Jatrophacurcas acyl-ACP thioesterase (GenBank Accession No. ABX82799.3), Zeamays oleoyl-acyl carrier protein thioesterase, (GenBank Accession No.ACG40089.1), Haematococcus pluvialis fatty acyl- ACP thioesterase(GenBank Accession No. HM560034.1) Desaturase Enzymes Linumusitatissimum fatty acid desaturase 3C, (GenBank Acc. No. ADV92272.1),Ricinus communis omega-3 fatty acid desaturase, endoplasmic reticulum,putative, (GenBank Acc. No. EEF36775.1), Vernicia fordii omega-3 fattyacid desaturase, (GenBank Acc. No. AAF12821), Glycine max chloroplastomega 3 fatty acid desaturase isoform 2, (GenBank Acc. No. ACF19424.1),Prototheca moriformis FAD-D omega 3 desaturase (SEQ ID NO: 221),Prototheca moriformis linoleate desaturase (SEQ ID NO: 220), Carthamustinctorius delta 12 desaturase, (GenBank Accession No. ADM48790.1),Gossypium hirsutum omega-6 desaturase, (GenBank Accession No.CAA71199.1), Glycine max microsomal desaturase (GenBank Accession No.BAD89862.1), Zea mays fatty acid desaturase (GenBank Accession No.ABF50053.1), Brassica napa linoleic acid desaturase (GenBank AccessionNo. AAA32994.1), Camelina sativa omega-3 desaturase (SEQ ID NO: 214),Prototheca moriformis delta 12 desaturase allele 2 (SEQ ID NO: 212),Camelina sativa omega-3 FAD7- 1 (SEQ ID NO: 215), Helianthus annuusstearoyl-ACP desaturase, (GenBank Accession No. AAB65145.1), Ricinuscommunis stearoyl-ACP desaturase, (GenBank Accession No. AACG59946.1),Brassica juncea plastidic delta-9-stearoyl-ACP desaturase (GenBankAccession No. AAD40245.1), Glycine max stearoyl-ACP desaturase (GenBankAccession No. ACJ39209.1), Olea europaea stearoyl-ACP desaturase(GenBank Accession No. AAB67840.1), Vernicia fordiistearoyl-acyl-carrier protein desaturase, (GenBank Accession No.ADC32803.1), Descurainia sophia delta-12 fatty acid desaturase (GenBankAccession No. ABS86964.2), Euphorbia lagascae delta12-oleic aciddesaturase (GenBank Acc. No. AAS57577.1), Chlorella vulgaris delta 12fatty acid desaturease (GenBank Accession No. ACF98528), Chlorellavulgaris omega-3 fatty acid desaturease (GenBank Accession No.BAB78717), Haematococcus pluvialis omega-3 fatty acid desaturase(GenBank Accession No. HM560035.1), Haematococcus pluvialisstearoyl-ACP-desaturase GenBank Accession No. EF586860.1, Haematococcuspluvialis stearoyl-ACP-desaturase GenBank Accession No. EF523479.1Oleate 12-hydroxylase Enzymes Ricinus communis oleate 12-hydroxylase(GenBank Acc. No. AAC49010.1), Physaria lindheimeri oleate12-hydroxylase (GenBank Acc. No. ABQ01458.1), Physaria lindheimerimutant bifunctional oleate 12-hydroxylase:desaturase (GenBank Acc. No.ACF17571.1), Physaria lindheimeri bifunctional oleate12-hydroxylase:desaturase (GenBank Accession No. ACQ42234.1), Physarialindheimeri bifunctional oleate 12- hydroxylase:desaturase (GenBank Acc.No. AAC32755.1), Arabidopsis lyrata subsp. Lyrata (GenBank Acc. No.XP_002884883.1)

Example 22: Engineering Chlorella vulgaris

Expression of recombinant genes in accordance with the present inventionin Chlorella vulgaris can be accomplished by modifying the methods andvectors taught by Chow and Tung et al. as discussed herein. Briefly,Chow and Tung et al., Plant Cell Reports, Volume 18 (1999), pp. 778-780,reported the stable nuclear transformation of Chlorella vulgaris withplasmid DNA. Using the transformation method of electroporation, Chowand Tung introduced the plasmid pIG121-Hm (GenBank Accession No.AB489142) into Chlorella vulgaris. The nucleotide sequence of pIG121-Hmcomprised sequence encoding a beta-glucuronidase (GUS) reporter geneproduct operably-linked to a CaMV 35S promoter upstream of the GUSprotein-coding sequence and further operably linked to the 3′UTR/terminator of the nopaline synthase (nos) gene downstream of the GUSprotein-coding sequence. The sequence of plasmid pIG121-Hm furthercomprised a hygromycin B antibiotic resistance cassette. This hygromycinB antibiotic resistance cassette comprised a CaMV 35S promoter operablylinked to sequence encoding the hygromycin phosphotransferase (hpt,GenBank Accession No. BAH24259) gene product. Prior to transformation,Chlorella vulgaris was unable to be propagated in culture mediumcomprising 50 ug/ml hygromycin B. Upon transformation with the pIG121-Hmplasmid, transformants of Chlorella vulgaris were obtained that werepropagated in culture medium comprising 50 ug/ml hyrgromycin B. Theexpression of the hpt gene product in Chlorella vulgaris enabledpropagation of transformed Chlorella vulgaris in the presence of 50ug/mL hyrgromycin B, thereby establishing the utility of the ahygromycin B resistance cassette as a selectable marker for use inChlorella vulgaris. Detectable activity of the GUS reporter geneindicated that CaMV 35S promoter and nos 3′UTR are suitable for enablingheterologous gene expression in Chlorella vulgaris. Evaluation of thegenomic DNA of the stable transformants was performed by Southernanalysis. Selection and maintenance of transformed Chlorella vulgariswas performed on agar plates comprising YA medium (agar and 4 g/L yeastextract). The propagation of Chlorella vulgaris in liquid culture mediumwas conducted as discussed by Chow and Tung. Propagation of Chlorellavulgaris in media other than YA medium has been described (for examples,see Chader et al., Revue des Energies Renouvelabes, Volume 14 (2011),pp. 21-26 and Illman et al., Enzyme and Microbial Technology, Vol. 27(2000), pp. 631-635). Chow and Tung reported that the plasmid pIG121-Hm,the CaMV 35S promoter, and the Agrobacterium tumefaciens nopalinesynthase gene 3′UTR/terminator are suitable to enable heterologous geneexpression in Chlorella vulgaris. In addition, Chow and Tung reportedthe hyromycin B resistance cassette was suitable for use as a selectablemarker in Chlorella vulgaris. Additional plasmids, promoters,3′UTR/terminators, and selectable markers suitable for enablingheterologous gene expression in Chlorella vulgaris have been discussedin Chader et al., Revue des Energies Renouvelabes, Volume 14 (2011), pp.21-26.

In an embodiment of the present invention, pIG121-Hm, comprising thenucleotide sequence encoding the hygromycin B gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Chlorella vulgaris to reflect thecodon bias inherent in nuclear genes of Chlorella vulgaris in accordancewith Tables 69A-D. For each lipid biosynthesis pathway protein of Table70, the codon-optimized gene sequence can individually be operablylinked to the CaMV 35S promoter upstream of the protein-coding sequenceand operably linked to the Agrobacterium tumefaciens nopaline synthasegene 3′UTR/terminator at the 3′ region, or downstream, of theprotein-coding sequence. The transformation construct may additionallycomprise homology regions to the Chlorella vulgaris genome for targetedgenomic integration of the transformation vector. Homology regions maybe selected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Chlorella vulgariswith the transformation vector is achieved through well-knowntransformation techniques including electroporation or other knownmethods. Activity of the hygromycin B resistance gene product can beused as a marker to select for Chlorella vulgaris transformed with thetransformation vector on, but not limited to, agar medium comprisinghygromycin. Growth media suitable for Chlorella vulgaris lipidproduction include, but are not limited to BG11 medium (0.04 g/L KH₂PO₄,0.075 g/L CaCl₂, 0.036 g/L citric acid, 0.006 g/L Ammonium FerricCitrate, 1 mg/L EDTA, and 0.02 g/L Na₂CO₃) supplemented with tracemetals, and optionally 1.5 g/L NaNO3. Additional media suitable forculturing Chlorella vulgaris for lipid production include, for example,Watanabe medium (comprising 1.5 g/L KNO₃, 1.25 g/L KH₂PO₄, 1.25 g 1⁻¹MgSO₄-7H₂O, 20 mg 1⁻¹ FeSO₄-7H₂O with micronutrients and low-nitrogenmedium (comprising 203 mg/l (NH₄)₂HPO₄, 2.236 g/l KCl, 2.465 g/l MgSO₄,1.361 g/l KH₂PO₄ and 10 mg/l FeSO₄) as reported by Illman et al., Enzymeand Microbial Technology, Vol. 27 (2000), pp. 631-635. Evaluation offatty acid profiles of Chlorella vulgaris lipids can be assessed throughstandard lipid extraction and analytical methods described herein.

Example 23: Engineering Chlorella ellipsoidea

Expression of recombinant genes in accordance with the present inventionin Chlorella ellipsoidea can be accomplished by modifying the methodsand vectors taught by Chen et al. as discussed herein. Briefly, Chen etal., Current Genetics, Vol. 39:5 (2001), pp. 365-370, reported thestable transformation of Chlorella ellipsoidea with plasmid DNA. Usingthe transformation method of electroporation, Chen introduced theplasmid pBinUΩNP-1 into Chlorella ellipsoidea. The nucleotide sequenceof pBinUΩNP-1 comprised sequence encoding the neutrophil peptide-1(NP-1) rabbit gene product operably linked to a Zea mays Ubiquitin(ubi1) gene promoter upstream of the NP-1 protein-coding region andoperably linked to the 3′ UTR/terminator of the nopaline synthase (nos)gene downstream of the NP-1 protein-coding region. The sequence ofplasmid pBinUΩNP-1 further comprised a G418 antibiotic resistancecassette. This G418 antibiotic resistance cassette comprised sequenceencoding the aminoglycoside 3′-phosphotransferase (aph 3′) gene product.The aph 3′ gene product confers resistance to the antibiotic G418. Priorto transformation, Chlorella ellipsoidea was unable to be propagated inculture medium comprising 30 ug/mL G418. Upon transformation with thepBinUΩNP-1 plasmid, transformants of Chlorella ellipsoidea were obtainedthat were propagated in selective culture medium comprising 30 ug/mLG418. The expression of the aph 3′ gene product in Chlorella ellipsoideaenabled propagation of transformed Chlorella ellipsoidea in the presenceof 30 ug/mL G418, thereby establishing the utility of the G418antibiotic resistance cassette as selectable marker for use in Chlorellaellipsoidea. Detectable activity of the NP-1 gene product indicated thatthe ubi1 promoter and nos 3′ UTR are suitable for enabling heterologousgene expression in Chlorella ellipsoidea. Evaluation of the genomic DNAof the stable transformants was performed by Southern analysis.Selection and maintenance of the transformed Chlorella ellipsoidea wasperformed on Knop medium (comprising 0.2 g/L K₂HPO₄, 0.2 g/L MgSO₄.7H₂O,0.12 g/L KCl, and 10 mg/L FeCl3, pH 6.0-8.0 supplemented with 0.1% yeastextract and 0.2% glucose) with 15 ug/mL G418 (for liquid cultures) orwith 30 ug/mL G418 (for solid cultures comprising 1.8% agar).Propagation of Chlorella ellipsoidea in media other than Knop medium hasbeen reported (see Cho et al., Fisheries Science, Vol. 73:5 (2007), pp.1050-1056, Jarvis and Brown, Current Genetics, Vol. 19 (1991), pp.317-321 and Kim et al., Marine Biotechnology, Vol. 4 (2002), pp. 63-73).Additional plasmids, promoters, 3′UTR/terminators, and selectablemarkers suitable for enabling heterologous gene expression in Chlorellaellipsoidea have been reported (see Jarvis and Brown and Kim et al.,Marine Biotechnology, Vol. 4 (2002), pp. 63-73). Chen reported that theplasmid pBinUΩNP-1, the ubi1 promoter, and the Agrobacterium tumefaciensnopaline synthase gene 3′UTR/terminator are suitable to enable exogenousgene expression in Chlorella ellipsoidea. In addition, Chen reportedthat the G418 resistance cassette encoded on pBinUΩNP-1 was suitable foruse as a selectable marker in Chlorella ellipsoidea.

In an embodiment of the present invention, vector pBinUΩNP-1, comprisingthe nucleotide sequence encoding the aph 3′ gene product, conferringresistance to G418, for use as a selectable marker, is constructed andmodified to further comprise a lipid biosynthesis pathway expressioncassette sequence, thereby creating a transformation vector. The lipidbiosynthesis pathway expression cassette encodes one or more lipidbiosynthesis pathway proteins selected from Table 70, eachprotein-coding sequence codon-optimized for expression in Chlorellaellipsoidea to reflect the codon bias inherent in nuclear genes ofChlorella ellipsoidea in accordance with Tables 69A-D. For each lipidbiosynthesis pathway protein of Table 70, the codon-optimized genesequence can individually be operably linked to the Zea mays ubi1promoter upstream of the protein-coding sequence and operably linked tothe Agrobacterium tumefaciens nopaline synthase gene 3′UTR/terminator atthe 3′ region, or downstream, of the protein-coding sequence. Thetransformation construct may additionally comprise homology regions tothe Chlorella ellipsoidea genome for targeted genomic integration of thetransformation vector. Homology regions may be selected to disrupt oneor more genomic sites of endogenous lipid biosynthesis pathway genes.Stable transformation of Chlorella ellipsoidea with the transformationvector is achieved through well-known transformation techniquesincluding electroporation or other known methods. Activity of the aph 3′gene product can be used as a marker to select for Chlorella ellipsoideatransformed with the transformation vector on, but not limited to, Knopagar medium comprising G418. Growth media suitable for Chlorellaellipsoidea lipid production include, but are not limited to, Knopmedium and those culture medium reported by Jarvis and Brown and Kim etal. Evaluation of fatty acid profiles of Chlorella ellipsoidea lipidscan be assessed through standard lipid extraction and analytical methodsdescribed herein.

Example 24: Engineering Chlorella kessleri

Expression of recombinant genes in accordance with the present inventionin Chlorella kessleri can be accomplished by modifying the methods andvectors taught by El-Sheekh et al. as discussed herein. Briefly,El-Sheekh et al., Biologia Plantarium, Vol. 42:2 (1999), pp. 209-216,reported the stable transformation of Chlorella kessleri with plasmidDNA. Using the transformation method of microprojectile bombardment,El-Sheekh introduced the plasmid pBI121 (GenBank Accession No. AF485783)into Chlorella kessleri. Plasmid pBI121 comprised a kanamycin/neomycinantibiotic resistance cassette. This kanamycin/neomycin antibioticresistance cassette comprised the Agrobacterium tumefaciens nopalinesynthase (nos) gene promoter, sequence encoding the neomycinphosphotransferase II (nptII) gene product (GenBank Accession No.AAL92039) for resistance to kanamycin and G418, and the 3′UTR/terminator of the Agrobacterium tumefaciens nopaline synthase (nos)gene. pBI121 further comprised sequence encoding a beta-glucuronidase(GUS) reporter gene product operably linked to a CaMV 35S promoter andoperably linked to a 3′ UTR/terminator of the nos gene. Prior totransformation, Chlorella kessleri was unable to be propagated inculture medium comprising 15 ug/L kanamycin. Upon transformation withthe pBI121 plasmid, transformants of Chlorella kessleri were obtainedthat were propagated in selective culture medium comprising 15 mg/Lkanamycin. The express ion of the nptII gene product in Chlorellakessleri enabled propagation in the presence of 15 mg/L kanamycin,thereby establishing the utility of the kanamycin/neomycin antibioticresistance cassette as selectable marker for use in Chlorella kessleri.Detectable activity of the GUS gene product indicated that the CaMV 35Spromoter and nos 3′ UTR are suitable for enabling heterologous geneexpression in Chlorella kessleri. Evaluation of the genomic DNA of thestable transformants was performed by Southern analysis. As reported byEl-Sheekh, selection and maintenance of transformed Chlorella kessleriwas conducted on semisolid agar plates comprising YEG medium (1% yeastextract, 1% glucose) and 15 mg/L kanamycin. El-Sheekh also reported thepropagation of Chlorella kessleri in YEG liquid culture media.Additional media suitable for culturing Chlorella kessleri for lipidproduction are disclosed in Sato et al., BBA Molecular and Cell Biologyof Lipids, Vol. 1633 (2003), pp. 27-34). El-Sheekh reported that theplasmid pBI121, the CaMV promoter, and the nopaline synthase gene3′UTR/terminator are suitable to enable heterologous gene expression inChlorella kessleri. In addition, El-Sheekh reported that thekanamycin/neomycin resistance cassette encoded on pBI121 was suitablefor use as a selectable marker in Chlorella kessleri.

In an embodiment of the present invention, vector pBI121, comprising thenucleotide sequence encoding the kanamycin/neomycin resistance geneproduct for use as a selectable marker, is constructed and modified tofurther comprise a lipid biosynthesis pathway expression cassettesequence, thereby creating a transformation vector. The lipidbiosynthesis pathway expression cassette encodes one or more lipidbiosynthesis pathway proteins selected from Table 70, eachprotein-coding sequence codon-optimized for expression in Chlorellakessleri to reflect the codon bias inherent in nuclear genes ofChlorella kessleri in accordance with Tables 69A-D. For each lipidbiosynthesis pathway protein of Table 70, the codon-optimized genesequence can individually be operably linked to the CaMV 35S promoterupstream of the protein-coding sequence and operably linked to theAgrobacterium tumefaciens nopaline synthase gene 3′UTR/terminator at the3′ region, or downstream, of the protein-coding sequence. Thetransformation construct may additionally comprise homology regions tothe Chlorella kessleri genome for targeted genomic integration of thetransformation vector. Homology regions may be selected to disrupt oneor more genomic sites of endogenous lipid biosynthesis pathway genes.Stable transformation of Chlorella kessleri with the transformationvector is achieved through well-known transformation techniquesincluding microprojectile bombardment or other known methods. Activityof the nptII gene product can be used as a marker to select forChlorella kessleri transformed with the transformation vector on, butnot limited to, YEG agar medium comprising kanamycin or neomycin. Growthmedia suitable for Chlorella kessleri lipid production include, but arenot limited to, YEG medium, and those culture media reported by Sato etal. Evaluation of fatty acid profiles of Chlorella kessleri lipids canbe assessed through standard lipid extraction and analytical methodsdescribed herein.

Example 25: Engineering Dunaliella tertiolecta

Expression of recombinant genes in accordance with the present inventionin Dunaliella tertiolecta can be accomplished by modifying the methodsand vectors taught by Walker et al. as discussed herein. Briefly, Walkeret al., Journal of Applied Phycology, Vol. 17 (2005), pp. 363-368,reported stable nuclear transformation of Dunaliella tertiolecta withplasmid DNA. Using the transformation method of electroporation, Walkerintroduced the plasmid pDbleFLAG1.2 into Dunaliella tertiolecta.pDbleFLAG1.2 comprised sequence encoding a bleomycin antibioticresistance cassette, comprising sequence encoding the Streptoalloteichushindustanus Bleomycin binding protein (ble), for resistance to theantibiotic phleomycin, operably linked to the promoter and 3′ UTR of theDunaliella tertiolecta ribulose-1,5-bisphosphate carboxylase/oxygenasesmall subunit gene (rbcS1, GenBank Accession No. AY530155). Prior totransformation, Dunaliella tertiolecta was unable to be propagated inculture medium comprising 1 mg/L phleomycin. Upon transformation withthe pDbleFLAG1.2 plasmid, transformants of Dunaliella tertiolecta wereobtained that were propagated in selective culture medium comprising 1mg/L phleomycin. The expression of the ble gene product in Dunaliellatertiolecta enabled propagation in the presence of 1 mg/L phleomycin,thereby establishing the utility of the bleomycin antibiotic resistancecassette as selectable marker for use in Dunaliella tertiolecta.Evaluation of the genomic DNA of the stable transformants was performedby Southern analysis. As reported by Walker, selection and maintenanceof transformed Dunaliella tertiolecta was conducted in Dunaliella medium(DM, as described by Provasoli et al., Archiv fur Mikrobiologie, Vol. 25(1957), pp. 392-428) further comprising 4.5 g/L NaCl and 1 mg/Lpheomycin. Additional media suitable for culturing Dunaliellatertiolecta for lipid production are discussed in Takagi et al., Journalof Bioscience and Bioengineering, Vol. 101:3 (2006), pp. 223-226 and inMassart and Hanston, Proceedings Venice 2010, Third InternationalSymposium on Energy from Biomass and Waste. Walker reported that theplasmid pDbleFLAG1.2 and the promoter and 3′ UTR of the Dunaliellatertiolecta ribulose-1,5-bisphosphate carboxylase/oxygenase smallsubunit gene are suitable to enable heterologous expression inDunaliella tertiolecta. In addition, Walker reported that the bleomycinresistance cassette encoded on pDbleFLAG1.2 was suitable for use as aselectable marker in Dunaliella tertiolecta.

In an embodiment of the present invention, vector pDbleFLAG1.2,comprising the nucleotide sequence encoding the ble gene product for useas a selectable marker, is constructed and modified to further comprisea lipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Dunaliella tertiolecta to reflect thecodon bias inherent in nuclear genes of Dunaliella tertiolecta inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the rbcS1 promoter upstream of the protein-codingsequence and operably linked to the rbcS1 3′UTR/terminator at the 3′region, or downstream, of the protein-coding sequence. Thetransformation construct may additionally comprise homology regions tothe Dunaliella tertiolecta genome for targeted genomic integration ofthe transformation vector. Homology regions may be selected to disruptone or more genomic sites of endogenous lipid biosynthesis pathwaygenes. Stable transformation of Dunaliella tertiolecta with thetransformation vector is achieved through well-known transformationtechniques including electroporation or other known methods. Activity ofthe ble gene product can be used as a marker to select for Dunaliellatertiolecta transformed with the transformation vector on, but notlimited to, DM medium comprising pheomycin. Growth medium suitable forDunaliella tertiolecta lipid production include, but are not limited toDM medium and those culture media described by Takagi et al. and Massartand Hanston. Evaluation of fatty acid profiles of Dunaliella tertiolectalipids can be assessed through standard lipid extraction and analyticalmethods described herein.

Example 26: Engineering Volvox carteri

Expression of recombinant genes in accordance with the present inventionin Volvox carteri can be accomplished by modifying the methods andvectors taught by Hallman and Rappel et al. as discussed herein.Briefly, Hallman and Rappel et al., The Plant Journal, Volume 17 (1999),pp. 99-109, reported the stable nuclear transformation of Volvox carteriwith plasmid DNA. Using the transformation method of microprojectilebombardment, Hallman and Rappel introduced the pzeoE plasmid into Volvoxcarteri. The pzeoE plasmid comprised sequence encoding a bleomycinantibiotic resistance cassette, comprising sequence encoding theStreptoalloteichus hindustanus Bleomycin binding protein (ble), forresistance to the antibiotic zeocin, operably linked to and the promoterand 3′ UTR of the Volvox carteri beta-tubulin gene (GenBank AccessionNo. L24547). Prior to transformation, Volvox carteri was unable to bepropagated in culture medium comprising 1.5 ug/ml zeocin. Upontransformation with the pzeoE plasmid, transformants of Volvox carteriwere obtained that were propagated in selective culture mediumcomprising greater than 20 ug/ml zeocin. The expression of the ble geneproduct in Volvox carteri enabled propagation in the presence of 20ug/ml zeocin, thereby establishing the utility of the bleomycinantibiotic resistance cassette as selectable marker for use in Volvoxcarteri. Evaluation of the genomic DNA of the stable transformants wasperformed by Southern analysis. As reported by Hallman and Rappel,selection and maintenance of transformed Volvox carteri was conducted inVolvox medium (VM, as described by Provasoli and Pintner, The Ecology ofAlgae, Special Publication No. 2 (1959), Tyron, C. A. and Hartman, R.T., eds., Pittsburgh: University of Pittsburgh, pp. 88-96) with 1 mg/Lpheomycin. Media suitable for culturing Volvox carteri for lipidproduction are also discussed by Starr in Starr R, C., Dev Biol Suppl.,Vol. 4 (1970), pp. 59-100). Hallman and Rappel reported that the plasmidpzeoE and the promoter and 3′ UTR of the Volvox carteri beta-tubulingene are suitable to enable heterologous expression in Volvox carteri.In addition, Hallman and Rappel reported that the bleomycin resistancecassette encoded on pzeoE was suitable for use as a selectable marker inVolvox carteri. Additional plasmids, promoters, 3′UTR/terminators, andselectable markers suitable for enabling heterologous gene expression inVolvox carteri and suitable for use as selective markers Volvox carteriin have been reported (for instance see Hallamann and Sumper,Proceedings of the National Academy of Sciences, Vol. 91 (1994), pp11562-11566 and Hallman and Wodniok, Plant Cell Reports, Volume 25(2006), pp. 582-581).

In an embodiment of the present invention, vector pzeoE, comprising thenucleotide sequence encoding the ble gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Volvox carteri to reflect the codonbias inherent in nuclear genes of Volvox carteri in accordance withTables 69A-D. For each lipid biosynthesis pathway protein of Table 70,the codon-optimized gene sequence can individually be operably linked tothe Volvox carteri beta-tubulin promoter upstream of the protein-codingsequence and operably linked to the Volvox carteri beta-tubulin3′UTR/terminator at the 3′ region, or downstream, of the protein-codingsequence. The transformation construct may additionally comprisehomology regions to the Volvox carteri genome for targeted genomicintegration of the transformation vector. Homology regions may beselected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. One skilled in the art can identify suchhomology regions within the sequence of the Volvox carteri genome(referenced in the publication by Prochnik et al., Science, Vol.329:5988 (2010), pp 223-226). Stable transformation of Volvox carteriwith the transformation vector is achieved through well-knowntransformation techniques including microprojectile bombardment or otherknown methods. Activity of the ble gene product can be used as a markerto select for Volvox carteri transformed with the transformation vectoron, but not limited to, VM medium comprising zeocin. Growth mediumsuitable for Volvox carteri lipid production include, but are notlimited to VM medium and those culture media discussed by Starr.Evaluation of fatty acid profiles of Volvox carteri lipids can beassessed through standard lipid extraction and analytical methodsdescribed herein.

Example 27: Engineering Haematococcus pluvialis

Expression of recombinant genes in accordance with the present inventionin Haematococcus pluvialis can be accomplished by modifying the methodsand vectors taught by Steinbrenner and Sandmann et al. as discussedherein. Briefly, Steinbrenner and Sandmann et al., Applied andEnvironmental Microbiology, Vol. 72:12 (2006), pp. 7477-7484, reportedthe stable nuclear transformation of Haematococcus pluvialis withplasmid DNA. Using the transformation method of microprojectilebombardment, Steinbrenner introduced the plasmid pPlat-pds-L504R intoHaematococcus pluvialis. The plasmid pPlat-pds-L504R comprised anorflurazon resistance cassette, which comprised the promoter,protein-coding sequence, and 3′UTR of the Haematococcus pluvialisphytoene desaturase gene (Pds, GenBank Accession No. AY781170), whereinthe protein-coding sequence of Pds was modified at position 504 (therebychanging a leucine to an arginine) to encode a gene product (Pds-L504R)that confers resistance to the herbicide norflurazon. Prior totransformation with pPlat-pds-L504R, Haematococcus pluvialis was unableto propagate on medium comprising 5 uM norflurazon. Upon transformationwith the pPlat-pds-L504R plasmid, transformants of Haematococcuspluvialis were obtained that were propagated in selective culture mediumcomprising 5 uM norflurazon. The expression of the Pds-L504R geneproduct in Haematococcus pluvialis enabled propagation in the presenceof 5 uM norflurazon, thereby establishing the utility of the norflurazonherbicide resistance cassette as selectable marker for use inHaematococcus pluvialis. Evaluation of the genomic DNA of the stabletransformants was performed by Southern analysis. As reported bySteinbrenner, selection and maintenance of transformed Haematococcuspluvialis was conducted on agar plates comprising OHA medium (OHM (0.41g/L KNO₃, 0.03 g/L Na₂HPO₄, 0.246 g/L MgSO₄-7H₂O, 0.11 g/L CaCl₂.2H₂O,2.62 mg/L Fe_((III))citrate×H₂O, 0.011 mg/L CoCl₂.6H₂O, 0.012 mg/LCuSO₄.5H₂O, 0.075 mg/L Cr₂O₃, 0.98 mg/L MnCl₂.4H₂O, 0.12 mg/LNa₂MoO₄×2H₂O, 0.005 mg/L SeO₂ and 25 mg/L biotin, 17.5 mg/L thiamine,and 15 mg/L vitamin B12), supplemented with 2.42 g/L Tris-acetate, and 5mM norflurazon. Propagation of Haematococcus pluvialis in liquid culturewas performed by Steinbrenner and Sandmann using basal medium (basalmedium as described by Kobayashi et al., Applied and EnvironmentalMicrobiology, Vol. 59 (1993), pp. 867-873). Steinbrenner and Sandmannreported that the pPlat-pds-L504R plasmid and promoter and 3′ UTR of theHaematococcus pluvialis phytoene desaturase gene are suitable to enableheterologous expression in Haematococcus pluvialis. In addition,Steinbrenner and Sandmann reported that the norflurazon resistancecassette encoded on pPlat-pds-L504R was suitable for use as a selectablemarker in Haematococcus pluvialis. Additional plasmids, promoters,3′UTR/terminators, and selectable markers suitable for enablingheterologous gene expression in Haematococcus pluvialis have beenreported (see Kathiresan et al., Journal of Phycology, Vol. 45 (2009),pp 642-649).

In an embodiment of the present invention, vector pPlat-pds-L504R,comprising the nucleotide sequence encoding the Pds-L504R gene productfor use as a selectable marker, is constructed and modified to furthercomprise a lipid biosynthesis pathway expression cassette sequence,thereby creating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Haematococcus pluvialis to reflect thecodon bias inherent in nuclear genes of Haematococcus pluvialis inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Haematococcus pluvialis pds gene promoterupstream of the protein-coding sequence and operably linked to theHaematococcus pluvialis pds gene 3′UTR/terminator at the 3′ region, ordownstream, of the protein-coding sequence. The transformation constructmay additionally comprise homology regions to the Haematococcuspluvialis genome for targeted genomic integration of the transformationvector. Homology regions may be selected to disrupt one or more genomicsites of endogenous lipid biosynthesis pathway genes. Stabletransformation of Haematococcus pluvialis with the transformation vectoris achieved through well-known transformation techniques includingmicroprojectile bombardment or other known methods. Activity of thePds-L504R gene product can be used as a marker to select forHaematococcus pluvialis transformed with the transformation vector on,but not limited to, OHA medium comprising norflurazon. Growth mediasuitable for Haematococcus pluvialis lipid production include, but arenot limited to basal medium and those culture media described byKobayashi et al., Kathiresan et al, and Gong and Chen, Journal ofApplied Phycology, Vol. 9:5 (1997), pp. 437-444). Evaluation of fattyacid profiles of Haematococcus pluvialis lipids can be assessed throughstandard lipid extraction and analytical methods described herein.

Example 28: Engineering Closterium peracerosum-strigosum-littoralecomplex

Expression of recombinant genes in accordance with the present inventionin Closterium peracerosum-strigosum-littorale complex can beaccomplished by modifying the methods and vectors taught by Abe et al.as discussed herein. Briefly, Abe et al., Plant Cell Physiology, Vol.52:9 (2011), pp. 1676-1685, reported the stable nuclear transformationof Closterium peracerosum-strigosum-littorale complex with plasmid DNA.Using the transformation methods of microprojectile bombardment, Abeintroduced the plasmid pSA106 into Closteriumperacerosum-strigosum-littorale complex. Plasmid pSA106 comprised ableomycin resistance cassette, comprising sequence encoding theStreptoalloteichus hindustanus Bleomycin binding protein gene (ble,GenBank Accession No. CAA37050) operably linked to the promoter and 3′UTR of the Closterium peracerosum-strigosum-littorale complexChlorophyll a/b-binding protein gene (CAB, GenBank Accession No.AB363403). Prior to transformation with pSA106, Closteriumperacerosum-strigosum-littorale complex was unable to propagate onmedium comprising 3 ug/ml phleomycin. Upon transformation with pSA106,transformants of Closterium peracerosum-strigosum-littorale complex wereobtained that were propagated in selective culture medium comprising 3ug/ml phleomycin. The expression of the ble gene product in Closteriumperacerosum-strigosum-littorale complex enabled propagation in thepresence of 3 ug/ml phleomycin, thereby establishing the utility of thebleomycin antibiotic resistance cassette as selectable marker for use inClosterium peracerosum-strigosum-littorale complex. Evaluation of thegenomic DNA of the stable transformants was performed by Southernanalysis. As reported by Abe, selection and maintenance of transformedClosterium peracerosum-strigosum-littorale complex was conducted firstin top agar with C medium (0.1 g/L KNO₃, 0.015 g/L Ca(NO₃)₂.4H2O, 0.05g/L glycerophosphate-Na2, 0.04 g/L MgSO₄.7H₂O, 0.5 g/L Tris(hydroxylmethyl) aminomethane, trace minerals, biotin, vitamins B₁ andB₁₂) and then subsequently isolated to agar plates comprising C mediumsupplemented with phleomycin. As reported by Abe, propagation ofClosterium peracerosum-strigosum-littorale complex in liquid culture wasperformed in C medium. Additional liquid culture medium suitable forpropagation of Closterium peracerosum-strigosum-littorale complex arediscussed by Sekimoto et al., DNA Research, 10:4 (2003), pp. 147-153.Abe reported that the pSA106 plasmid and promoter and 3′ UTR of theClosterium peracerosum-strigosum-littorale complex CAB gene are suitableto enable heterologous gene expression in Closteriumperacerosum-strigosum-littorale complex. In addition, Abe reported thatthe bleomycin resistance cassette encoded on pSA106 was suitable for useas a selectable marker in Closterium peracerosum-strigosum-littoralecomplex. Additional plasmids, promoters, 3′UTR/terminators, andselectable markers suitable for enabling heterologous gene expression inClosterium peracerosum-strigosum-littorale complex have been reported(see Abe et al., Plant Cell Physiology, Vol. 49 (2008), pp. 625-632).

In an embodiment of the present invention, vector pSA106, comprising thenucleotide sequence encoding the ble gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Closteriumperacerosum-strigosum-littorale complex to reflect the codon biasinherent in nuclear genes of Closterium peracerosum-strigosum-littoralecomplex in accordance with Tables 69A-D. For each lipid biosynthesispathway protein of Table 70, the codon-optimized gene sequence canindividually be operably linked to the Closteriumperacerosum-strigosum-littorale complex CAB gene promoter upstream ofthe protein-coding sequence and operably linked to the Closteriumperacerosum-strigosum-littorale complex CAB gene 3′UTR/terminator at the3′ region, or downstream, of the protein-coding sequence. Thetransformation construct may additionally comprise homology regions tothe Closterium peracerosum-strigosum-littorale complex genome fortargeted genomic integration of the transformation vector. Homologyregions may be selected to disrupt one or more genomic sites ofendogenous lipid biosynthesis pathway genes. Stable transformation ofClosterium peracerosum-strigosum-littorale complex with thetransformation vector is achieved through well-known transformationtechniques including microprojectile bombardment or other known methods.Activity of the ble gene product can be used as a marker to select forClosterium peracerosum-strigosum-littorale complex transformed with thetransformation vector on, but not limited to, C medium comprisingphleomycin. Growth media suitable for Closteriumperacerosum-strigosum-littorale complex lipid production include, butare not limited to C medium and those culture media reported by Abe etal. and Sekimoto et al. Evaluation of fatty acid profiles of Closteriumperacerosum-strigosum-littorale complex lipids can be assessed throughstandard lipid extraction and analytical methods described herein.

Example 29: Engineering Dunaliella viridis

Expression of recombinant genes in accordance with the present inventionin Dunaliella viridis can be accomplished by modifying the methods andvectors taught by Sun et al. as discussed herein. Briefly, Sun et al.,Gene, Vol. 377 (2006), pp. 140-149, reported the stable transformationof Dunaliella viridis with plasmid DNA. Using the transformation methodof electoporation, Sun introduced the plasmid pDVNR, encoding the fullDunaliella viridis nitrate reductase gene into mutant Dunaliella viridis(Dunaliella viridis NR-mutants.) The NR-mutants are incapable of growthwithout the use of nitrate as a source of nitrogen. Nitrate reductasecatalyzes the conversion of nitrate to nitrite. Prior to transformation,Dunaliella viridis NR-mutants were unable to propagate in culture mediumcomprising nitrate (NO₃ ⁻) as the sole nitrogen source. The expressionof the Dunaliella viridis NR gene product in NR-mutant Dunaliellaviridis was used as a selectable marker to rescue the nitrate metabolismdeficiency. Upon transformation with the pDVNR plasmid, NR-mutantDunaliella viridis stably expressing the Dunaliella viridis NR geneproduct were obtained that were able to grow on agar plates comprisingnitrate as the sole carbon source. Evaluation of the DNA of the stabletransformants was performed by Southern analysis. Selection andmaintenance of the transformed Dunaliella viridis (NR mutant) wasperformed on agar plates comprising 5 mM KNO₃. Sun also reported thepropagation of Dunaliella viridis and Dunaliella viridis NR mutants inliquid culture medium. Additional media suitable for propagation ofDunaliella viridis are reported by Gordillo et al., Journal of AppliedPhycology, Vol. 10:2 (1998), pp. 135-144 and by Moulton and Burford,Hydrobiologia, Vols. 204-205:1 (1990), pp. 401-408. Sun reported thatthe plasmid pDVNR and the promoter and 3′ UTR/terminator of theDunaliella viridis nitrate reductase gene were suitable to enableheterologous expression in Dunaliella viridis NR-mutants. Sun alsoreported that expression of the Dunaliella viridis nitrate reductasegene product was suitable for use as a selectable marker in Dunaliellaviridis NR-mutants.

In an embodiment of the present invention, vector pDVNR, comprising thenucleotide sequence encoding the Dunaliella viridis nitrate reductase(DvNR) gene product for use as a selectable marker, is constructed andmodified to further comprise a lipid biosynthesis pathway expressioncassette sequence, thereby creating a transformation vector. The lipidbiosynthesis pathway expression cassette encodes one or more lipidbiosynthesis pathway proteins selected from Table 70, eachprotein-coding sequence codon-optimized for expression in Dunaliellaviridis to reflect the codon bias inherent in nuclear genes ofDunaliella viridis in accordance with Tables 69A-D. For each lipidbiosynthesis pathway protein of Table 70, the codon-optimized genesequence can individually be operably linked to the DvNR promoterupstream of the protein-coding sequence and operably linked to the DvNR3′UTR/terminator at the 3′ region, or downstream, of the protein-codingsequence. The transformation construct may additionally comprisehomology regions to the Dunaliella viridis genome for targeted genomicintegration of the transformation vector. Homology regions may beselected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Dunaliella viridisNR mutants with the transformation vector is achieved through well-knowntransformation techniques including electorporation or other knownmethods. Activity of the DvNR gene product can be used as a selectablemarker to rescue the nitrogen assimilation deficiency of Dunaliellaviridis NR mutant strains and to select for Dunaliella viridisNR-mutants stably expressing the transformation vector. Growth mediasuitable for Dunaliella viridis lipid production include, but are notlimited to those discussed by Sun et al., Moulton and Burford, andGordillo et al. Evaluation of fatty acid profiles of Dunaliella viridislipids can be assessed through standard lipid extraction and analyticalmethods described herein.

Example 30: Engineering Dunaliella salina

Expression of recombinant genes in accordance with the present inventionin Dunaliella salina can be accomplished by modifying the methods andvectors taught by Geng et al. as discussed herein. Briefly, Geng et al.,Journal of Applied Phycology, Vol. 15 (2003), pp. 451-456, reported thestable transformation of Dunaliella salina with plasmid DNA. Using thetransformation method of electroporation, Geng introduced thepUΩHBsAg-CAT plasmid into Dunaliella salina. pUΩHBsAg-CAT comprises ahepatitis B surface antigen (HBsAG) expression cassette comprisingsequence encoding the hepatitis B surface antigen operably linked to aZea mays ubi1 promoter upstream of the HBsAG protein-coding region andoperably linked to the 3′UTR terminator of the Agrobacterium tumefaciensnopaline synthase gene (nos) downstream of the HBsAG protein-codingregion. pUΩHBsAg-CAT further comprised a chloramphenicol resistancecassette, comprising sequence encoding the chloramphenicolacetyltransferase (CAT) gene product, conferring resistance to theantibiotic chloramphenicol, operably linked to the simian virus 40promoter and enhancer. Prior to transformation with pUΩHBsAg-CAT,Dunaliella salina was unable to propagate on medium comprising 60 mg/Lchloramphenicol. Upon transformation with the pUΩHBsAg-CAT plasmid,transformants of Dunaliella salina were obtained that were propagated inselective culture medium comprising 60 mg/L chloramphenicol. Theexpression of the CAT gene product in Dunaliella salina enabledpropagation in the presence of 60 mg/L chloramphenicol, therebyestablishing the utility of the chloramphenicol resistance cassette asselectable marker for use in Dunaliella salina. Detectable activity ofthe HBsAg gene product indicated that ubi1 promoter and nos3′UTR/terminator are suitable for enabling gene expression in Dunaliellasalina. Evaluation of the genomic DNA of the stable transformants wasperformed by Southern analysis. Geng reported that selection andmaintenance of the transformed Dunaliella salina was performed on agarplates comprising Johnson's medium (J1, described by Borowitzka andBorowitzka (eds), Micro-algal Biotechnology. Cambridge University Press,Cambridge, pp. 460-461) with 60 mg/L chloramphenicol. Liquid propagationof Dunaliella salina was performed by Geng in J1 medium with 60 mg/Lchloramphenicol. Propagation of Dunaliella salina in media other than J1medium has been discussed (see Feng et al., Mol. Bio. Reports, Vol. 36(2009), pp. 1433-1439 and Borowitzka et al., Hydrobiologia, Vols.116-117:1 (1984), pp. 115-121). Additional plasmids, promoters,3′UTR/terminators, and selectable markers suitable for enablingheterologous gene expression in Dunaliella salina have been reported byFeng et al. Geng reported that the plasmid pUΩHBsAg-CAT, the ubi1promoter, and the Agrobacterium tumefaciens nopaline synthase gene3′UTR/terminator are suitable to enable exogenous gene expression inDunaliella salina. In addition, Geng reported that the CAT resistancecassette encoded on pUΩHBsAg-CAT was suitable for use as a selectablemarker in Dunaliella salina.

In an embodiment of the present invention, vector pUΩHBsAg-CAT,comprising the nucleotide sequence encoding the CAT gene product for useas a selectable marker, is constructed and modified to further comprisea lipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Dunaliella salina to reflect the codonbias inherent in nuclear genes of Dunaliella salina in accordance withTables 69A-D. For each lipid biosynthesis pathway protein of Table 70,the codon-optimized gene sequence can individually be operably linked tothe ubi1 promoter upstream of the protein-coding sequence and operablylinked to the Agrobacterium tumefaciens nopaline synthase gene3′UTR/terminator at the 3′ region, or downstream, of the protein-codingsequence. The transformation construct may additionally comprisehomology regions to the Dunaliella salina genome for targeted genomicintegration of the transformation vector. Homology regions may beselected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Dunaliella salinawith the transformation vector is achieved through well-knowntransformation techniques including electroporation or other knownmethods. Activity of the CAT gene product can be used as a selectablemarker to select for Dunaliella salina transformed with thetransformation vector in, but not limited to, J1 medium comprisingchrloramphenicol. Growth medium suitable for Dunaliella salina lipidproduction include, but are not limited to J1 medium and those culturemedia described by Feng et al. and Borowitzka et al. Evaluation of fattyacid profiles of Dunaliella salina lipids can be assessed throughstandard lipid extraction and analytical methods described herein.

Example 31: Engineering Gonium pectoral

Expression of recombinant genes in accordance with the present inventionin Gonium pectoral can be accomplished by modifying the methods andvectors taught by Lerche and Hallman et al. as discussed herein.Briefly, Lerche and Hallman et al., BMC Biotechnology, Volume 9:64,2009, reported the stable nuclear transformation of Gonium pectoralewith plasmid DNA. Using the transformation method of microprojectilebombardment, Lerche introduced the plasmid pPmr3 into Gonium pectorale.Plasmid pPmr3 comprised a paromomycin resistance cassette, comprising asequence encoding the aminoglycoside 3′-phosphotransferase (aphVIII)gene product (GenBank Accession No. AAB03856) of Streptomyces rimosusfor resistance to the antibiotic paromomycin, operably linked to theVolvox carteri hsp70A-rbcS3 hybrid promoter upstream of the aphVIIIprotein-coding region and operably linked to the 3′ UTR/terminator ofthe Volvox carteri rbcS3 gene downstream of the aphVIII protein-codingregion. Prior to transformation with pPmr3, Gonium pectorale was unableto propagate on medium comprising 0.06 ug/ml paromomycin. Upontransformation with pPmr3, transformants of Gonium pectorale wereobtained that were propagated in selective culture medium comprising0.75 and greater ug/ml paromomycin. The expression of the aphVIII geneproduct in Gonium pectorale enabled propagation in the presence of 0.75and greater ug/ml paromomycin, thereby establishing the utility of theparomomycin antibiotic resistance cassette as selectable marker for usein Gonium pectorale. Evaluation of the genomic DNA of the stabletransformants was performed by Southern analysis. Lerche and Hallmanreported that selection and maintenance of the transformed Goniumpectorale was performed in liquid Jaworski's medium (20 mg/LCa(NO₃)₂.4H₂O, 12.4 mg/L KH₂PO₄, 50 mg/L MgSO₄.7H₂O, 15.9 mg/L NaHCO₃,2.25 mg/L EDTA-FeNa, 2.25 mg/L EDTA Na₂, 2.48 g/L H₃BO₃, 1.39 g/LMnCl₂.4H₂O, 1 mg/L (NH₄)₆MO₇O₂4.4H₂O, 0.04 mg/L vitamin B12, 0.04 mg/LThiamine-HCl, 0.04 mg/L biotin, 80 mg/L NaNO₃, 36 mg/L Na₄HPO₄.12H₂O)with 1.0 ug/ml paromomycin. Additional plasmids, promoters,3′UTR/terminators, and selectable markers suitable for enablingheterologous gene expression in Gonium pectorale are further discussedby Lerche and Hallman. Lerche and Hallman reported that the plasmidpPmr3, Volvox carteri hsp70A-rbcS3 hybrid promoter, and the 3′UTR/terminator of the Volvox carteri rbcS3 gene are suitable to enableexogenous gene expression in Gonium pectorale. In addition, Lerche andHallman reported that the paromomycin resistance cassette encoded pPmr3was suitable for use as a selectable marker in Gonium pectorale.

In an embodiment of the present invention, vector pPmr3, comprising thenucleotide sequence encoding the aphVIII gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Gonium pectorale to reflect the codonbias inherent in nuclear genes of Gonium pectorale in accordance withTables 69A-D. For each lipid biosynthesis pathway protein of Table 70,the codon-optimized gene sequence can individually be operably linked tothe Volvox carteri hsp70A-rbcS3 hybrid promoter upstream of theprotein-coding sequence and operably linked to the Volvox carteri rbcS3gene 3′UTR/terminator at the 3′ region, or downstream, of theprotein-coding sequence. The transformation construct may additionallycomprise homology regions to the Gonium pectorale genome for targetedgenomic integration of the transformation vector. Homology regions maybe selected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Gonium pectoralewith the transformation vector can be achieved through well-knowntransformation techniques including microprojectile bombardment or otherknown methods. Activity of the aphVIII gene product can be used as aselectable marker to select for Gonium pectorale transformed with thetransformation vector in, but not limited to, Jaworski's mediumcomprising paromomycin. Growth media suitable for Gonium pectorale lipidproduction include Jawaorski's medium and media reported by Stein,American Journal of Botany, Vol. 45:9 (1958), pp. 664-672. Evaluation offatty acid profiles of Gonium pectorale lipids can be assessed throughstandard lipid extraction and analytical methods described herein.

Example 32: Engineering Phaeodactylum tricornutum

Expression of recombinant genes in accordance with the present inventionin Phaeodactylum tricornutum can be accomplished by modifying themethods and vectors taught by Apt et al. as discussed herein. Briefly,Apt et al., Molecular and General Genetics, Vol. 252 (1996), pp.572-579, reported the stable nuclear transformation of Phaeodactylumtricornutum with vector DNA. Using the transformation technique ofmicroprojectile bombardment, Apt introduced the plasmid pfcpA intoPhaeodactylum tricornutum. Plasmid pfcpA comprised a bleomycinresistance cassette, comprising sequence encoding the Streptoalloteichushindustanus Bleomycin binding protein (ble), for resistance to theantibiotics phleomycin and zeocin, operably linked to the promoter ofthe Phaeodactylum tricornutum fucoxanthin chlorophyll a binding proteingene (fcpA) upstream of the ble protein-coding region and operablylinked to the 3′ UTR/terminator of the Phaeodactylum tricornutum fcpAgene at the 3′ region, or downstream of the ble protein-coding region.Prior to transformation with pfcpA, Phaeodactylum tricornutum was unableto propagate on medium comprising 50 ug/ml zeocin. Upon transformationwith pfcpA, transformants of Phaeodactylum tricornutum were obtainedthat were propagated in selective culture medium comprising 50 ug/mlzeocin. The expression of the ble gene product in Phaeodactylumtricornutum enabled propagation in the presence of 50 ug/ml zeocin,thereby establishing the utility of the bleomycin antibiotic resistancecassette as selectable marker for use in Phaeodactylum tricornutum.Evaluation of the genomic DNA of the stable transformants was performedby Southern analysis. Apt reported that selection and maintenance of thetransformed Phaeodactylum tricornutum was performed on agar platescomprising LDM medium (as reported by Starr and Zeikus, Journal ofPhycology, Vol. 29, Supplement, (1993)) with 50 mg/L zeocin. Aptreported liquid propagation of Phaeodactylum tricornutum transformantsin LDM medium with 50 mg/L zeocin. Propagation of Phaeodactylumtricornutum in medium other than LDM medium has been discussed (byZaslavskaia et al., Science, Vol. 292 (2001), pp. 2073-2075, and byRadokovits et al., Metabolic Engineering, Vol. 13 (2011), pp. 89-95).Additional plasmids, promoters, 3′UTR/terminators, and selectablemarkers suitable for enabling heterologous gene expression inPhaeodactylum tricornutum have been reported in the same report by Aptet al., by Zaslavskaia et al., and by Radokovits et al.). Apt reportedthat the plasmid pfcpA, and the Phaeodactylum tricornutum fcpA promoterand 3′ UTR/terminator are suitable to enable exogenous gene expressionin Phaeodactylum tricornutum. In addition, Apt reported that thebleomycin resistance cassette encoded on pfcpA was suitable for use as aselectable marker in Phaeodactylum tricornutum.

In an embodiment of the present invention, vector pfcpA, comprising thenucleotide sequence encoding the ble gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Phaeodactylum tricornutum to reflectthe codon bias inherent in nuclear genes of Phaeodactylum tricornutum inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Phaeodactylum tricornutum fcpA gene promoterupstream of the protein-coding sequence and operably linked to thePhaeodactylum tricornutum fcpA gene 3′UTR/terminator at the 3′ region,or downstream, of the protein-coding sequence. The transformationconstruct may additionally comprise homology regions to thePhaeodactylum tricornutum genome for targeted genomic integration of thetransformation vector. Homology regions may be selected to disrupt oneor more genomic sites of endogenous lipid biosynthesis pathway genes.One skilled in the art can identify such homology regions within thesequence of the Phaeodactylum tricornutum genome (referenced in thepublication by Bowler et al., Nature, Vol. 456 (2008), pp. 239-244).Stable transformation of Phaeodactylum tricornutum with thetransformation vector is achieved through well-known transformationtechniques including microprojectile bombardment or other known methods.Activity of the ble gene product can be used as a marker to select forPhaeodactylum tricornutum transformed with the transformation vector in,but not limited to, LDM medium comprising paromomycin. Growth mediumsuitable for Phaeodactylum tricornutum lipid production include, but arenot limited to f/2 medium as reported by Radokovits et al. Evaluation offatty acid profiles of Phaeodactylum tricornutum lipids can be assessedthrough standard lipid extraction and analytical methods describedherein.

Example 33: Engineering Chaetoceros sp.

Expression of recombinant genes in accordance with the present inventionin Chaetoceros sp. can be accomplished by modifying the methods andvectors taught by Yamaguchi et al. as discussed herein. Briefly,Yamaguchi et al., Phycological Research, Vol. 59:2 (2011), pp. 113-119,reported the stable nuclear transformation of Chaetoceros sp. withplasmid DNA. Using the transformation method of microprojectilebombardment, Yamaguchi introduced the plasmid pTpfcp/nat intoChaetoceros sp. pTpfcp/nat comprised a nourseothricin resistancecassette, comprising sequence encoding the nourseothricinacetyltransferase (nat) gene product (GenBank Accession No. AAC60439)operably linked to the Thalassiosira pseudonana fucoxanthin chlorophylla/c binding protein gene (fcp) promoter upstream of the natprotein-coding region and operably linked to the Thalassiosirapseudonana fcp gene 3′ UTR/terminator at the 3′ region (downstream ofthe nat protein coding-sequence). The nat gene product confersresistance to the antibiotic nourseothricin. Prior to transformationwith pTpfcp/nat, Chaetoceros sp. was unable to propagate on mediumcomprising 500 ug/ml nourseothricin. Upon transformation withpTpfcp/nat, transformants of Chaetoceros sp. were obtained that werepropagated in selective culture medium comprising 500 ug/mlnourseothricin. The expression of the nat gene product in Chaetocerossp. enabled propagation in the presence of 500 ug/ml nourseothricin,thereby establishing the utility of the nourseothricin antibioticresistance cassette as selectable marker for use in Chaetoceros sp.Evaluation of the genomic DNA of the stable transformants was performedby Southern analysis. Yamaguchi reported that selection and maintenanceof the transformed Chaetoceros sp. was performed on agar platescomprising f/2 medium (as reported by Guilard, R. R., Culture ofPhytoplankton for feeding marine invertebrates, In Culture of MarineInvertebrate Animals, Smith and Chanley (eds) 1975, Plenum Press, NewYork, pp. 26-60) with 500 ug/ml nourseothricin. Liquid propagation ofChaetoceros sp. transformants, as performed by Yamaguchi, was carriedout in f/2 medium with 500 mg/L nourseothricin. Propagation ofChaetoceros sp. in additional culture medium has been reported (forexample in Napolitano et al., Journal of the World Aquaculture Society,Vol. 21:2 (1990), pp. 122-130, and by Volkman et al., Journal ofExperimental Marine Biology and Ecology, Vol. 128:3 (1989), pp.219-240). Additional plasmids, promoters, 3′UTR/terminators, andselectable markers suitable for enabling heterologous gene expression inChaetoceros sp. have been reported in the same report by Yamaguchi etal. Yamaguchi reported that the plasmid pTpfcp/nat, and theThalassiosira pseudonana fcp promoter and 3′ UTR/terminator are suitableto enable exogenous gene expression in Chaetoceros sp. In addition,Yamaguchi reported that the nourseothricin resistance cassette encodedon pTpfcp/nat was suitable for use as a selectable marker in Chaetocerossp.

In an embodiment of the present invention, vector pTpfcp/nat, comprisingthe nucleotide sequence encoding the nat gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in the closely-related Chaetoceroscompressum to reflect the codon bias inherent in nuclear genes ofChaetoceros compressum in accordance with Tables 69A-D. For each lipidbiosynthesis pathway protein of Table 70, the codon-optimized genesequence can individually be operably linked to the Thalassiosirapseudonana fcp gene promoter upstream of the protein-coding sequence andoperably linked to the Thalassiosira pseudonana fcp gene3′UTR/terminator at the 3′ region, or downstream, of the protein-codingsequence. The transformation construct may additionally comprisehomology regions to the Chaetoceros sp. genome for targeted genomicintegration of the transformation vector. Homology regions may beselected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Chaetoceros sp.with the transformation vector is achieved through well-knowntransformation including microprojectile bombardment or other knownmethods. Activity of the nat gene product can be used as a selectablemarker to select for Chaetoceros sp. transformed with the transformationvector in, but not limited to, f/2 agar medium comprisingnourseothricin. Growth medium suitable for Chaetoceros sp. lipidproduction include, but are not limited to, f/2 medium, and thoseculture media discussed by Napolitano et al. and Volkman et al.Evaluation of fatty acid profiles of Chaetoceros sp lipids can beassessed through standard lipid extraction and analytical methodsdescribed herein.

Example 34: Engineering Cylindrotheca fusiformis

Expression of recombinant genes in accordance with the present inventionin Cylindrotheca fusiformis can be accomplished by modifying the methodsand vectors taught by Poulsen and Kroger et al. as discussed herein.Briefly, Poulsen and Kroger et al., FEBS Journal, Vol. 272 (2005), pp.3413-3423, reported the transformation of Cylindrotheca fusiformis withplasmid DNA. Using the transformation method of microprojectilebombardment, Poulsen and Kroger introduced the pCF-ble plasmid intoCylindrotheca fusiformis. Plasmid pCF-ble comprised a bleomycinresistance cassette, comprising sequence encoding the Streptoalloteichushindustanus Bleomycin binding protein (ble), for resistance to theantibiotics zeocin and phleomycin, operably linked to the Cylindrothecafusiformis fucozanthin chlorophyll a/c binding protein gene (fcpA,GenBank Accession No. AY125580) promoter upstream of the bleprotein-coding region and operably linked to the Cylindrothecafusiformis fcpA gene 3′UTR/terminator at the 3′ region (down-stream ofthe ble protein-coding region). Prior to transformation with pCF-ble,Cylindrotheca fusiformis was unable to propagate on medium comprising 1mg/ml zeocin. Upon transformation with pCF-ble, transformants ofCylindrotheca fusiformis were obtained that were propagated in selectiveculture medium comprising 1 mg/ml zeocin. The expression of the ble geneproduct in Cylindrotheca fusiformis enabled propagation in the presenceof 1 mg/ml zeocin, thereby establishing the utility of the bleomycinantibiotic resistance cassette as selectable marker for use inCylindrotheca fusiformis. Poulsen and Kroger reported that selection andmaintenance of the transformed Cylindrotheca fusiformis was performed onagar plates comprising artificial seawater medium with 1 mg/ml zeocin.Poulsen and Kroger reported liquid propagation of Cylindrothecafusiformis transformants in artificial seawater medium with 1 mg/mlzeocin. Propagation of Cylindrotheca fusiformis in additional culturemedium has been discussed (for example in Liang et al., Journal ofApplied Phycology, Vol. 17:1 (2005), pp. 61-65, and by Orcutt andPatterson, Lipids, Vol. 9:12 (1974), pp. 1000-1003). Additionalplasmids, promoters, and 3′UTR/terminators for enabling heterologousgene expression in Chaetoceros sp. have been reported in the same reportby Poulsen and Kroger. Poulsen and Kroger reported that the plasmidpCF-ble and the Cylindrotheca fusiformis fcp promoter and 3′UTR/terminator are suitable to enable exogenous gene expression inCylindrotheca fusiformis. In addition, Poulsen and Kroger reported thatthe bleomycin resistance cassette encoded on pCF-ble was suitable foruse as a selectable marker in Cylindrotheca fusiformis.

In an embodiment of the present invention, vector pCF-ble, comprisingthe nucleotide sequence encoding the ble gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Cylindrotheca fusiformis to reflectthe codon bias inherent in nuclear genes of Cylindrotheca fusiformis inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Cylindrotheca fusiformis fcp gene promoterupstream of the protein-coding sequence and operably linked to theCylindrotheca fusiformis fcp gene 3′UTR/terminator at the 3′ region, ordownstream, of the protein-coding sequence. The transformation constructmay additionally comprise homology regions to the Cylindrothecafusiformis genome for targeted genomic integration of the transformationvector. Homology regions may be selected to disrupt one or more genomicsites of endogenous lipid biosynthesis pathway genes. Stabletransformation of Cylindrotheca fusiformis with the transformationvector is achieved through well-known transformation techniquesincluding microprojectile bombardment or other known methods. Activityof the ble gene product can be used as a selectable marker to select forCylindrotheca fusiformis transformed with the transformation vector in,but not limited to, artificial seawater agar medium comprising zeocin.Growth media suitable for Cylindrotheca fusiformis lipid productioninclude, but are not limited to, artificial seawater and those mediareported by Liang et al. and Orcutt and Patterson. Evaluation of fattyacid profiles of Cylindrotheca fusiformis lipids can be assessed throughstandard lipid extraction and analytical methods described herein.

Example 35: Engineering Amphidinium sp.

Expression of recombinant genes in accordance with the present inventionin Amphidinium sp. can be accomplished by modifying the methods andvectors taught by ten Lohuis and Miller et al. as discussed herein.Briefly, ten Lohuis and Miller et al., The Plant Journal, Vol. 13:3(1998), pp. 427-435, reported the stable transformation of Amphidiniumsp. with plasmid DNA. Using the transformation technique of agitation inthe presence of silicon carbide whiskers, ten Lohuis introduced theplasmid pMT NPT/GUS into Amphidinium sp. pMT NPT/GUS comprised aneomycin resistance cassette, comprising sequence encoding the neomycinphosphotransferase II (nptII) gene product (GenBank Accession No.AAL92039) operably linked to the Agrobacterium tumefaciens nopalinesynthase (nos) gene promoter upstream, or 5′ of the nptII protein-codingregion and operably linked to the 3′ UTR/terminator of the nos gene atthe 3′ region (down-stream of the nptII protein-coding region). ThenptII gene product confers resistance to the antibiotic G418. The pMTNPT/GUS plasmid further comprised sequence encoding a beta-glucuronidase(GUS) reporter gene product operably-linked to a CaMV 35S promoter andfurther operably linked to the CaMV 35S 3′ UTR/terminator. Prior totransformation with pMT NPT/GUS, Amphidinium sp. was unable to bepropagated on medium comprising 3 mg/ml G418. Upon transformation withpMT NPT/GUS, transformants of Amphidinium sp. were obtained that werepropagated in selective culture medium comprising 3 mg/ml G418. Theexpression of the nptII gene product in Amphidinium sp. enabledpropagation in the presence of 3 mg/ml G418, thereby establishing theutility of the neomycin antibiotic resistance cassette as selectablemarker for use in Amphidinium sp. Detectable activity of the GUSreporter gene indicated that CaMV 35S promoter and 3′UTR are suitablefor enabling gene expression in Amphidinium sp. Evaluation of thegenomic DNA of the stable transformants was performed by Southernanalysis. ten Lohuis and Miller reported liquid propagation ofAmphidinium sp transformants in medium comprising seawater supplementedwith F/2 enrichment solution (provided by the supplier Sigma) and 3mg/ml G418 as well as selection and maintenance of Amphidinium sp.transformants on agar medium comprising seawater supplemented with F/2enrichment solution and 3 mg/ml G418. Propagation of Amphidinium sp. inadditional culture medium has been reported (for example in Mansour etal., Journal of Applied Phycology, Vol. 17:4 (2005) pp. 287-v300). Anadditional plasmid, comprising additional promoters, 3′UTR/terminators,and a selectable marker for enabling heterologous gene expression inAmphidinium sp. have been reported in the same report by ten Lohuis andMiller. ten Lohuis and Miller reported that the plasmid pMT NPT/GUS andthe promoter and 3′ UTR/terminator of the nos and CaMV 35S genes aresuitable to enable exogenous gene expression in Amphidinium sp. Inaddition, ten Lohuis and Miller reported that the neomycin resistancecassette encoded on pMT NPT/GUS was suitable for use as a selectablemarker in Amphidinium sp.

In an embodiment of the present invention, vector pMT NPT/GUS,comprising the nucleotide sequence encoding the nptII gene product foruse as a selectable marker, is constructed and modified to furthercomprise a lipid biosynthesis pathway expression cassette sequence,thereby creating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Amphidinium sp. to reflect the codonbias inherent in nuclear genes of the closely-related species,Amphidinium carterae in accordance with Tables 69A-D. For each lipidbiosynthesis pathway protein of Table 70, the codon-optimized genesequence can individually be operably linked to the Agrobacteriumtumefaciens nopaline synthase (nos) gene promoter upstream of theprotein-coding sequence and operably linked to the nos 3′UTR/terminatorat the 3′ region, or downstream, of the protein-coding sequence. Thetransformation construct may additionally comprise homology regions tothe Amphidinium sp. genome for targeted genomic integration of thetransformation vector. Homology regions may be selected to disrupt oneor more genomic sites of endogenous lipid biosynthesis pathway genes.Stable transformation of Amphidinium sp. with the transformation vectoris achieved through well-known transformation techniques includingsilicon fibre-mediated microinjection or other known methods. Activityof the nptII gene product can be used as a selectable marker to selectfor Amphidinium sp. transformed with the transformation vector in, butnot limited to, seawater agar medium comprising G418. Growth mediasuitable for Amphidinium sp. lipid production include, but are notlimited to, artificial seawater and those media reported by Mansour etal. and ten Lohuis and Miller. Evaluation of fatty acid profiles ofAmphidinium sp. lipids can be assessed through standard lipid extractionand analytical methods described herein.

Example 36: Engineering Symbiodinium microadriacticum

Expression of recombinant genes in accordance with the present inventionin Symbiodinium microadriacticum can be accomplished by modifying themethods and vectors taught by ten Lohuis and Miller et al. as discussedherein. Briefly, ten Lohuis and Miller et al., The Plant Journal, Vol.13:3 (1998), pp. 427-435, reported the stable transformation ofSymbiodinium microadriacticum with plasmid DNA. Using the transformationtechnique of silicon fibre-mediated microinjection, ten Lohuisintroduced the plasmid pMT NPT/GUS into Symbiodinium microadriacticum.pMT NPT/GUS comprised a neomycin resistance cassette, comprisingsequence encoding the neomycin phosphotransferase II (nptII) geneproduct (GenBank Accession No. AAL92039) operably linked to theAgrobacterium tumefaciens nopaline synthase (nos) gene promoterupstream, or 5′ of the nptII protein-coding region and operably linkedto the 3′ UTR/terminator of the nos gene at the 3′ region (down-streamof the nptII protein-coding region). The nptII gene product confersresistance to the antibiotic G418. The pMT NPT/GUS plasmid furthercomprised sequence encoding a beta-glucuronidase (GUS) reporter geneproduct operably-linked to a CaMV 35S promoter and further operablylinked to the CaMV 35S 3′ UTR/terminator. Prior to transformation withpMT NPT/GUS, Symbiodinium microadriacticum was unable to be propagatedon medium comprising 3 mg/ml G418. Upon transformation with pMT NPT/GUS,transformants of Symbiodinium microadriacticum were obtained that werepropagated in selective culture medium comprising 3 mg/ml G418. Theexpression of the nptII gene product in Symbiodinium microadriacticumenabled propagation in the presence of 3 mg/ml G418, therebyestablishing the utility of the neomycin antibiotic resistance cassetteas selectable marker for use in Symbiodinium microadriacticum.Detectable activity of the GUS reporter gene indicated that CaMV 35Spromoter and 3′UTR are suitable for enabling gene expression inSymbiodinium microadriacticum. Evaluation of the genomic DNA of thestable transformants was performed by Southern analysis. ten Lohuis andMiller reported liquid propagation of Symbiodinium microadriacticumtransformants in medium comprising seawater supplemented with F/2enrichment solution (provided by the supplier Sigma) and 3 mg/ml G418 aswell as selection and maintenance of Symbiodinium microadriacticumtransformants on agar medium comprising seawater supplemented with F/2enrichment solution and 3 mg/ml G418. Propagation of Symbiodiniummicroadriacticum in additional culture medium has been discussed (forexample in Iglesias-Prieto et al., Proceedings of the National Academyof Sciences, Vol. 89:21 (1992) pp. 10302-10305). An additional plasmid,comprising additional promoters, 3′UTR/terminators, and a selectablemarker for enabling heterologous gene expression in Symbiodiniummicroadriacticum have been discussed in the same report by ten Lohuisand Miller. ten Lohuis and Miller reported that the plasmid pMT NPT/GUSand the promoter and 3′ UTR/terminator of the nos and CaMV 35S genes aresuitable to enable exogenous gene expression in Symbiodiniummicroadriacticum. In addition, ten Lohuis and Miller reported that theneomycin resistance cassette encoded on pMT NPT/GUS was suitable for useas a selectable marker in Symbiodinium microadriacticum.

In an embodiment of the present invention, vector pMT NPT/GUS,comprising the nucleotide sequence encoding the nptII gene product foruse as a selectable marker, is constructed and modified to furthercomprise a lipid biosynthesis pathway expression cassette sequence,thereby creating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Symbiodinium microadriacticum. toreflect the codon bias inherent in nuclear genes of Symbiodiniummicroadriacticum in accordance with Tables 69A-D. For each lipidbiosynthesis pathway protein of Table 70, the codon-optimized genesequence can individually be operably linked to the Agrobacteriumtumefaciens nopaline synthase (nos) gene promoter upstream of theprotein-coding sequence and operably linked to the nos 3′UTR/terminatorat the 3′ region, or downstream, of the protein-coding sequence. Thetransformation construct may additionally comprise homology regions tothe Symbiodinium microadriacticum genome for targeted genomicintegration of the transformation vector. Homology regions may beselected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Symbiodiniummicroadriacticum with the transformation vector is achieved throughwell-known transformation techniques including silicon fibre-mediatedmicroinjection or other known methods. Activity of the nptII geneproduct can be used as a selectable marker to select for Symbiodiniummicroadriacticum transformed with the transformation vector in, but notlimited to, seawater agar medium comprising G418. Growth media suitablefor Symbiodinium microadriacticum lipid production include, but are notlimited to, artificial seawater and those media reported byIglesias-Prieto et al. and ten Lohuis and Miller. Evaluation of fattyacid profiles of Symbiodinium microadriacticum lipids can be assessedthrough standard lipid extraction and analytical methods describedherein.

Example 37: Engineering Nannochloropsis sp.

Expression of recombinant genes in accordance with the present inventionin Nannochloropsis sp. W2J3B can be accomplished by modifying themethods and vectors taught by Kilian et al. as discussed herein.Briefly, Kilian et al., Proceedings of the National Academy of Sciences,Vol. 108:52 (2011) pp. 21265-21269, reported the stable nucleartransformation of Nannochloropsis with a transformation construct. Usingthe transformation method of electroporation, Kilian introduced thetransformation construct C2 into Nannochloropsis sp. W2J3B. The C2transformation construct comprised a bleomycin resistance cassette,comprising the coding sequence for the Streptoalloteichus hindustanusBleomycin binding protein (ble), for resistance to the antibioticsphleomycin and zeocin, operably linked to and the promoter of theNannochloropsis sp. W2J3B violaxanthin/chlorophyll a-binding proteingene VCP2 upstream of the ble protein-coding region and operably linkedto the 3′UTR/terminator of the Nannochloropsis sp. W2J3Bviolaxanthin/chlorophyll a-binding gene VCP1 downstream of the bleprotein-coding region. Prior to transformation with C2, Nannochloropsissp. W2J3B was unable to propagate on medium comprising 2 ug/ml zeocin.Upon transformation with C2, transformants of Nannochloropsis sp. W2J3Bwere obtained that were propagated in selective culture mediumcomprising 2 ug/ml zeocin. The expression of the ble gene product inNannochloropsis sp. W2J3B enabled propagation in the presence of 2 ug/mlzeocin, thereby establishing the utility of the bleomycin antibioticresistance cassette as selectable marker for use in Nannochloropsis.Evaluation of the genomic DNA of the stable transformants was performedby PCR. Kilian reported liquid propagation of Nannochloropsis sp. W2J3Btransformants in F/2 medium (reported by Guilard and Ryther, CanadianJournal of Microbiology, Vol. 8 (1962), pp. 229-239) comprising fivefoldlevels of trace metals, vitamins, and phosphate solution, and furthercomprising 2 ug/ml zeocin. Kilian also reported selection andmaintenance of Nannochloropsis sp. W2J3B transformants on agar F/2medium comprising artificial seawater 2 mg/ml zeocin. Propagation ofNannochloropsis in additional culture medium has been discussed (forexample in Chiu et al., Bioresour Technol., Vol. 100:2 (2009), pp.833-838 and Pal et al., Applied Microbiology and Biotechnology, Vol.90:4 (2011), pp. 1429-1441.). Additional transformation constructs,comprising additional promoters and 3′UTR/terminators for enablingheterologous gene expression in Nannochloropsis sp. W2J3B and selectablemarkers for selection of transformants have been described in the samereport by Kilian. Kilian reported that the transformation construct C2and the promoter of the Nannochloropsis sp. W2J3Bviolaxanthin/chlorophyll a-binding protein gene VCP2 and 3′UTR/terminator of the Nannochloropsis sp. W2J3B violaxanthin/chlorophylla-binding protein gene VCP1 are suitable to enable exogenous geneexpression in Nannochloropsis sp. W2J3B. In addition, Kilian reportedthat the bleomycin resistance cassette encoded on C2 was suitable foruse as a selectable marker in Nannochloropsis sp. W2J3B.

In an embodiment of the present invention, transformation construct C2,comprising the nucleotide sequence encoding the ble gene product for useas a selectable marker, is constructed and modified to further comprisea lipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Nannochloropsis sp. W2J3B to reflectthe codon bias inherent in nuclear genes of Nannochloropsis sp. inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Nannochloropsis sp. W2J3B VCP2 gene promoterupstream of the protein-coding sequence and operably linked to theNannochloropsis sp. W2J3B VCP1 gene 3′UTR/terminator at the 3′ region,or downstream, of the protein-coding sequence. The transformationconstruct may additionally comprise homology regions to theNannochloropsis sp. W2J3B genome for targeted genomic integration of thetransformation vector. Homology regions may be selected to disrupt oneor more genomic sites of endogenous lipid biosynthesis pathway genes.Stable transformation of Nannochloropsis sp. W2J3B with thetransformation vector is achieved through well-known transformationtechniques including electroporation or other known methods. Activity ofthe ble gene product can be used as a selectable marker to select forNannochloropsis sp. W2J3B transformed with the transformation vector in,but not limited to, F/2 medium comprising zeocin. Growth media suitablefor Nannochloropsis sp. W2J3B lipid production include, but are notlimited to, F/2 medium and those media reported by Chiu et al. and Palet al. Evaluation of fatty acid profiles of Nannochloropsis sp. W2J3Blipids can be assessed through standard lipid extraction and analyticalmethods described herein.

Example 38: Engineering Cyclotella cryptica

Expression of recombinant genes in accordance with the present inventionin Cyclotella cryptica can be accomplished by modifying the methods andvectors taught by Dunahay et al. as discussed herein. Briefly, Dunahayet al., Journal of Phycology, Vol. 31 (1995), pp. 1004-1012, reportedthe stable transformation of Cyclotella cryptica with plasmid DNA. Usingthe transformation method of microprojectile bombardment, Dunahayintroduced the plasmid pACCNPT5.1 into Cyclotella cryptica. PlasmidpACCNPT5.1 comprised a neomycin resistance cassette, comprising thecoding sequence of the neomycin phosphotransferase II (nptII) geneproduct operably linked to the promoter of the Cyclotella crypticaacetyl-CoA carboxylase (ACCase) gene (GenBank Accession No. L20784)upstream of the nptII coding-region and operably linked to the3′UTR/terminator of the Cyclotella cryptica ACCase gene at the 3′ region(downstream of the nptII coding-region). The nptII gene product confersresistance to the antibiotic G418. Prior to transformation withpACCNPT5.1, Cyclotella cryptica was unable to propagate on 50%artificial seawater medium comprising 100 ug/ml G418. Upontransformation with pACCNPT5.1, transformants of Cyclotella crypticawere obtained that were propagated in selective 50% artificial seawatermedium comprising 100 ug/ml G418. The expression of the nptII geneproduct in Cyclotella cryptica enabled propagation in the presence of100 ug/ml G418, thereby establishing the utility of the neomycinantibiotic resistance cassette as selectable marker for use inCyclotella cryptica. Evaluation of the genomic DNA of the stabletransformants was performed by Southern analysis. Dunahay reportedliquid propagation of Cyclotella cryptica in artificial seawater medium(ASW, as discussed by Brown, L., Phycologia, Vol. 21 (1982), pp.408-410) supplemented with 1.07 mM sodium silicate and with 100 ug/mlG418. Dunahay also reported selection and maintenance of Cyclotellacryptica transformants on agar plates comprising ASW medium with 100ug/ml G418. Propagation of Cyclotella cryptica in additional culturemedium has been discussed (for example in Sriharan et al., AppliedBiochemistry and Biotechnology, Vol. 28-29:1 (1991), pp. 317-326 andPahl et al., Journal of Bioscience and Bioengineering, Vol. 109:3(2010), pp. 235-239). Dunahay reported that the plasmid pACCNPT5.1 andthe promoter of the Cyclotella cryptica acetyl-CoA carboxylase (ACCase)gene are suitable to enable exogenous gene expression in Cyclotellacryptica. In addition, Dunahay reported that the neomycin resistancecassette encoded on pACCNPT5.1 was suitable for use as a selectablemarker in Cyclotella cryptica.

In an embodiment of the present invention, vector pACCNPT5.1, comprisingthe nucleotide sequence encoding the nptII gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Cyclotella cryptica to reflect thecodon bias inherent in nuclear genes of Cyclotella cryptica inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Cyclotella cryptica ACCase promoter upstreamof the protein-coding sequence and operably linked to the Cyclotellacryptica ACCase 3′UTR/terminator at the 3′ region, or downstream, of theprotein-coding sequence. The transformation construct may additionallycomprise homology regions to the Cyclotella cryptica genome for targetedgenomic integration of the transformation vector. Homology regions maybe selected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. Stable transformation of Cyclotella crypticawith the transformation vector is achieved through well-knowntransformation techniques including microprojectile bombardment or otherknown methods. Activity of the nptII gene product can be used as amarker to select for Cyclotella cryptica transformed with thetransformation vector in, but not limited to, agar ASW medium comprisingG418. Growth media suitable for Cyclotella cryptica lipid productioninclude, but are not limited to, ASW medium and those media reported bySriharan et al., 1991 and Pahl et al. Evaluation of fatty acid profilesof Cyclotella cryptica lipids can be assessed through standard lipidextraction and analytical methods described herein.

Example 39: Engineering Navicula saprophila

Expression of recombinant genes in accordance with the present inventionin Navicula saprophila can be accomplished by modifying the methods andvectors taught by Dunahay et al. as discussed herein. Briefly, Dunahayet al., Journal of Phycology, Vol. 31 (1995), pp. 1004-1012, reportedthe stable transformation of Navicula saprophila with plasmid DNA. Usingthe transformation method of microprojectile bombardment, Dunahayintroduced the plasmid pACCNPT5.1 into Navicula saprophila. PlasmidpACCNPT5.1 comprised a neomycin resistance cassette, comprising thecoding sequence of the neomycin phosphotransferase II (nptII) geneproduct operably linked to the promoter of the Cyclotella crypticaacetyl-CoA carboxylase (ACCase) gene (GenBank Accession No. L20784)upstream of the nptII coding-region and operably linked to the3′UTR/terminator of the Cyclotella cryptica ACCase gene at the 3′ region(downstream of the nptII coding-region). The nptII gene product confersresistance to the antibiotic G418. Prior to transformation withpACCNPT5.1, Navicula saprophila was unable to propagate on artificialseawater medium comprising 100 ug/ml G418. Upon transformation withpACCNPT5.1, transformants of Navicula saprophila were obtained that werepropagated in selective artificial seawater medium comprising 100 ug/mlG418. The expression of the nptII gene product in Navicula saprophilaenabled propagation in the presence of G418, thereby establishing theutility of the neomycin antibiotic resistance cassette as selectablemarker for use in Navicula saprophila. Evaluation of the genomic DNA ofthe stable transformants was performed by Southern analysis. Dunahayreported liquid propagation of Navicula saprophila in artificialseawater medium (ASW, as discussed by Brown, L., Phycologia, Vol. 21(1982), pp. 408-410) supplemented with 1.07 mM sodium silicate and with100 ug/ml G418. Dunahay also reported selection and maintenance ofNavicula saprophila transformants on agar plates comprising ASW mediumwith 100 ug/ml G418. Propagation of Navicula saprophila in additionalculture medium has been discussed (for example in Tadros and Johansen,Journal of Phycology, Vol. 24:4 (1988), pp. 445-452 and Sriharan et al.,Applied Biochemistry and Biotechnology, Vol. 20-21:1 (1989), pp.281-291). Dunahay reported that the plasmid pACCNPT5.1 and the promoterof the Cyclotella cryptica acetyl-CoA carboxylase (ACCase) gene aresuitable to enable exogenous gene expression in Navicula saprophila. Inaddition, Dunahay reported that the neomycin resistance cassette encodedon pACCNPT5.1 was suitable for use as a selectable marker in Naviculasaprophila.

In an embodiment of the present invention, vector pACCNPT5.1, comprisingthe nucleotide sequence encoding the nptII gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Navicula saprophila to reflect thecodon bias inherent in nuclear genes of the closely-related Naviculapelliculosa in accordance with Tables 69A-D. For each lipid biosynthesispathway protein of Table 70, the codon-optimized gene sequence canindividually be operably linked to the Cyclotella cryptica ACCase genepromoter upstream of the protein-coding sequence and operably linked tothe Cyclotella cryptica ACCase gene 3′UTR/terminator at the 3′ region,or downstream, of the protein-coding sequence. The transformationconstruct may additionally comprise homology regions to the Naviculasaprophila genome for targeted genomic integration of the transformationvector. Homology regions may be selected to disrupt one or more genomicsites of endogenous lipid biosynthesis pathway genes. Stabletransformation of Navicula saprophila with the transformation vector isachieved through well-known transformation techniques includingmicroprojectile bombardment or other known methods. Activity of thenptII gene product can be used as a selectable marker to select forNavicula saprophila transformed with the transformation vector in, butnot limited to, agar ASW medium comprising G418. Growth media suitablefor Navicula saprophila lipid production include, but are not limitedto, ASW medium and those media reported by Sriharan et al. 1989 andTadros and Johansen. Evaluation of fatty acid profiles of Naviculasaprophila lipids can be assessed through standard lipid extraction andanalytical methods described herein.

Example 40: Engineering Thalassiosira pseudonana

Expression of recombinant genes in accordance with the present inventionin Thalassiosira pseudonana can be accomplished by modifying the methodsand vectors taught by Poulsen et al. as discussed herein. Briefly,Poulsen et al., Journal of Phycology, Vol. 42 (2006), pp. 1059-1065,reported the stable transformation of Thalassiosira pseudonana withplasmid DNA. Using the transformation method of microprojectilebombardment, Poulsen introduced the plasmid pTpfcp/nat in toThalassiosira pseudonana. pTpfcp/nat comprised a nourseothricinresistance cassette, comprising sequence encoding the nourseothricinacetyltransferase (nat) gene product (GenBank Accession No. AAC60439)operably linked to the Thalassiosira pseudonana fucoxanthin chlorophylla/c binding protein gene (fcp) promoter upstream of the natprotein-coding region and operably linked to the Thalassiosirapseudonana fcp gene 3′ UTR/terminator at the 3′ region (downstream ofthe nat protein coding-sequence). The nat gene product confersresistance to the antibiotic nourseothricin. Prior to transformationwith pTpfcp/nat, Thalassiosira pseudonana was unable to propagate onmedium comprising 10 ug/ml nourseothricin. Upon transformation withpTpfcp/nat, transformants of Thalassiosira pseudonana were obtained thatwere propagated in selective culture medium comprising 100 ug/mlnourseothricin. The expression of the nat gene product in Thalassiosirapseudonana enabled propagation in the presence of 100 ug/mlnourseothricin, thereby establishing the utility of the nourseothricinantibiotic resistance cassette as selectable marker for use inThalassiosira pseudonana. Evaluation of the genomic DNA of the stabletransformants was performed by Southern analysis. Poulsen reported thatselection and maintenance of the transformed Thalassiosira pseudonanawas performed in liquid culture comprising modified ESAW medium (asdiscussed by Harrison et al., Journal of Phycology, Vol. 16 (1980), pp.28-35) with 100 ug/ml nourseothricin. Propagation of Thalassiosirapseudonana in additional culture medium has been discussed (for examplein Volkman et al., Journal of Experimental Marine Biology and Ecology,Vol. 128:3 (1989), pp. 219-240). An additional plasmid, comprisingadditional selectable markers suitable for use in Thalassiosirapseudonana has been discussed in the same report by Poulsen. Poulsenreported that the plasmid pTpfcp/nat, and the Thalassiosira pseudonanafcp promoter and 3′ UTR/terminator are suitable to enable exogenous geneexpression in Thalassiosira pseudonana. In addition, Poulsen reportedthat the nourseothricin resistance cassette encoded on pTpfcp/nat wassuitable for use as a selectable marker in Thalassiosira pseudonana.

In an embodiment of the present invention, vector pTpfcp/nat, comprisingthe nucleotide sequence encoding the nat gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Thalassiosira pseudonana to reflectthe codon bias inherent in nuclear genes of Thalassiosira pseudonana inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Thalassiosira pseudonana fcp gene promoterupstream of the protein-coding sequence and operably linked to theThalassiosira pseudonana fcp gene 3′UTR/terminator at the 3′ region, ordownstream, of the protein-coding sequence. The transformation constructmay additionally comprise homology regions to the Thalassiosirapseudonana genome for targeted genomic integration of the transformationvector. Homology regions may be selected to disrupt one or more genomicsites of endogenous lipid biosynthesis pathway genes. One skilled in theart can identify such homology regions within the sequence of theThalassiosira pseudonana genome (referenced in the publication byArmbrust et al., Science, Vol. 306: 5693 (2004): pp. 79-86). Stabletransformation of Thalassiosira pseudonana with the transformationvector is achieved through well-known transformation techniquesincluding microprojectile bombardment or other known methods. Activityof the nat gene product can be used as a marker to select forThalassiosira pseudonana transformed with the transformation vector inbut not limited to, ESAW agar medium comprising nourseothricin. Growthmedia suitable for Thalassiosira pseudonana lipid production include,but are not limited to, ESAW medium, and those culture media discussedby Volkman et al. and Harrison et al. Evaluation of fatty acid profilesof Thalassiosira pseudonana lipids can be assessed through standardlipid extraction and analytical methods described herein.

Example 41: Engineering Chlamydomonas reinhardtii

Expression of recombinant genes in accordance with the present inventionin Chlamydomonas reinhardtii can be accomplished by modifying themethods and vectors taught by Cerutti et al. as discussed herein.Briefly, Cerutti et al., Genetics, Vol. 145:1 (1997), pp. 97-110,reported the stable nuclear transformation of Chlamydomonas reinhardtiiwith a transformation vector. Using the transformation method ofmicroprojectile bombardment, Cerutti introduced transformation constructP[1030] into Chlamydomonas reinhardtii. Construct P[1030] comprised aspectinomycin resistance cassette, comprising sequence encoding theaminoglucoside 3″-adenyltransferase (aadA) gene product operably linkedto the Chlamydomonas reinhardtii ribulose-1,5-bisphosphatecarboxylase/oxygenase small subunit gene (RbcS2, GenBank Accession No.X04472) promoter upstream of the aadA protein-coding region and operablylinked to the Chlamydomonas reinhardtii RbcS2 gene 3′ UTR/terminator atthe 3′ region (downstream of the aadA protein coding-sequence). The aadAgene product confers resistance to the antibiotic spectinomycin. Priorto transformation with P[1030], Chlamydomonas reinhardtii was unable topropagate on medium comprising 90 ug/ml spectinomycin. Upontransformation with P[1030], transformants of Chlamydomonas reinhardtiiwere obtained that were propagated in selective culture mediumcomprising 90 ug/ml spectinomycin, thereby establishing the utility ofthe spectinomycin antibiotic resistance cassette as a selectable markerfor use in Chlamydomonas reinhardtii. Evaluation of the genomic DNA ofthe stable transformants was performed by Southern analysis. Ceruttireported that selection and maintenance of the transformed Chlamydomonasreinhardtii was performed on agar plates comprisingTris-acetate-phosphate medium (TAP, as described by Harris, TheChlamydomonas Sourcebook, Academic Press, San Diego, 1989) with 90 ug/mlspectinomycin. Cerutti additionally reported propagation ofChlamydomonas reinhardtii in TAP liquid culture with 90 ug/mlspectinomycin. Propagation of Chlamydomonas reinhardtii in alternativeculture medium has been discussed (for example in Dent et al., AfricanJournal of Microbiology Research, Vol. 5:3 (2011), pp. 260-270 andYantao et al., Biotechnology and Bioengineering, Vol. 107:2 (2010), pp.258-268). Additional constructs, comprising additional selectablemarkers suitable for use in Chlamydomonas reinhardtii as well asnumerous regulatory sequences, including promoters and 3′ UTRs suitablefor promoting heterologous gene expression in Chlamydomonas reinhardtiiare known in the art and have been discussed (for a review, seeRadakovits et al., Eurkaryotic Cell, Vol. 9:4 (2010), pp. 486-501).Cerutti reported that the transformation vector P[1030] and theChlamydomonas reinhardtii promoter and 3′ UTR/terminator are suitable toenable exogenous gene expression in Chlamydomonas reinhardtii. Inaddition, Cerutti reported that the spectinomycin resistance cassetteencoded on P[1030] was suitable for use as a selectable marker inChlamydomonas reinhardtii.

In an embodiment of the present invention, vector P[1030], comprisingthe nucleotide sequence encoding the aadA gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Chlamydomonas reinhardtii to reflectthe codon bias inherent in nuclear genes of Chlamydomonas reinhardtii inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Chlamydomonas reinhardtii RbcS2 promoterupstream of the protein-coding sequence and operably linked to theChlamydomonas reinhardtii RbcS2 3′UTR/terminator at the 3′ region, ordownstream, of the protein-coding sequence. The transformation constructmay additionally comprise homology regions to the Chlamydomonasreinhardtii genome for targeted genomic integration of thetransformation vector. Homology regions may be selected to disrupt oneor more genomic site of an endogenous lipid biosynthesis pathway gene.One skilled in the art can identify such homology regions within thesequence of the Chlamydomonas reinhardtii genome (referenced in thepublication by Merchant et al., Science, Vol. 318:5848 (2007), pp.245-250). Stable transformation of Chlamydomonas reinhardtii with thetransformation vector is achieved through well-known transformationtechniques including microprojectile bombardment or other known methods.Activity of the aadA gene product can be used as a marker to select forChlamydomonas reinhardtii transformed with the transformation vector on,but not limited to, TAP agar medium comprising spectinomycin. Growthmedia suitable for Chlamydomonas reinhardtii lipid production include,but are not limited to, ESAW medium, and those culture media discussedby Yantao et al. and Dent et al. Evaluation of fatty acid profiles ofChlamydomonas reinhardtii lipids can be assessed through standard lipidextraction and analytical methods described herein.

Example 42: Engineering Yarrowia lipolytica

Expression of recombinant genes in accordance with the present inventionin Yarrowia lipolytica can be accomplished by modifying the methods andvectors taught by Fickers et al. as discussed herein. Briefly, Fickerset al., Journal of Microbiological Methods, Vol. 55 (2003), pp. 727-737,reported the stable nuclear transformation of Yarrowia lipolytica withplasmid DNA. Using a lithium acetate transformation method, Fickersintroduced the plasmid JMP123 into Yarrowia lipolytica. Plasmid JMP123comprised a hygromycin B resistance cassette, comprising sequenceencoding the hygromycin B phosphotransferase gene product (hph),operably-linked to the Yarrowia lipolytica LIP2 gene promoter (GenBankAccession No. AJ012632) upstream of the hph protein-coding region andoperably linked to the Yarrowia lipolytica LIP2 gene 3′UTR/terminatordownstream of the hph protein-coding region. Prior to transformationwith JMP123, Yarrowia lipolytica were unable to propagate on mediumcomprising 100 ug/ml hygromycin. Upon transformation with JMP123,transformed Yarrowia lipolytica were obtained that were able topropagate on medium comprising 100 ug/ml hygromycin, therebyestablishing the hygromycin B antibiotic resistance cassette as aselectable marker for use in Yarrowia lipolytica. The nucleotidesequence provided on JMP123 of the promoter and 3′UTR/terminator of theYarrowia lipolytica LIP2 gene served as donor sequences for homologousrecombination of the hph coding sequence into the LIP2 locus. Evaluationof the genomic DNA of the stable transformants was performed bySouthern. Fickers reported that selection and maintenance of thetransformed Yarrowia lipolytica was performed on agar plates comprisingstandard YPD medium (Yeast Extract Peptone Dextrose) with 100 ug/mlhygromycin. Liquid culturing of transformed Yarrowia lipolytica wasperformed in YPD medium with hygromycin. Other media and techniques usedfor culturing Yarrowia lipolytica have been reported and numerous otherplasmids, promoters, 3′ UTRs, and selectable markers for use in Yarrowialipolytica have been reported (for example see Pignede et al., Appliedand Environmental Biology, Vol. 66:8 (2000), pp. 3283-3289, Chuang etal., New Biotechnology, Vol. 27:4 (2010), pp. 277-282, and Barth andGaillardin, (1996), In: K,W. (Ed.), Nonconventional Yeasts inBiotechnology. Sprinter-Verlag, Berlin-Heidelber, pp. 313-388). Fickersreported that the transformation vector JMP123 and the Yarrowialipolytica LIP2 gene promoter and 3′ UTR/terminator are suitable toenable heterologous gene expression in Yarrowia lipolytica. In addition,Fickers reported that the hygromycin resistance cassette encoded onJMP123 was suitable for use as a selectable marker in Yarrowialipolytica.

In an embodiment of the present invention, vector JMP123, comprising thenucleotide sequence encoding the hph gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Yarrowia lipolytica to reflect thecodon bias inherent in nuclear genes of Yarrowia lipolytica inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the Yarrowia lipolytica LIP2 gene promoterupstream of the protein-coding sequence and operably linked to theYarrowia lipolytica LIP2 gene 3′UTR/terminator at the 3′ region, ordownstream, of the protein-coding sequence. The transformation constructmay additionally comprise homology regions to the Yarrowia lipolyticagenome for targeted genomic integration of the transformation vector.Homology regions may be selected to disrupt one or more genomic sites ofendogenous lipid biosynthesis pathway genes. One skilled in the art canidentify such homology regions within the sequence of the Yarrowialipolytica genome (referenced in the publication by Dujun et al.,Nature, Vol. 430 (2004), pp. 35-44). Stable transformation of Yarrowialipolytica with the transformation vector is achieved through well-knowntransformation techniques including lithium acetate transformation orother known methods. Activity of the hph gene product can be used as amarker to select for Yarrowia lipolytica transformed with thetransformation vector on, but not limited to, YPD medium comprisinghygromycin. Growth media suitable for Yarrowia lipolytica lipidproduction include, but are not limited to, YPD medium, and thoseculture media described by Chuang et al. Evaluation of fatty acidprofiles of Yarrowia lipolytica lipids can be assessed through standardlipid extraction and analytical methods described herein.

Example 43: Engineering Mortierella alpine

Expression of recombinant genes in accordance with the present inventionin Mortierella alpine can be accomplished by modifying the methods andvectors taught by Mackenzie et al. as discussed herein. Briefly,Mackenzie et al., Applied and Environmental Microbiology, Vol. 66(2000), pp. 4655-4661, reported the stable nuclear transformation ofMortierella alpina with plasmid DNA. Using a protoplast transformationmethod, MacKenzie introduced the plasmid pD4 into Mortierella alpina.Plasmid pD4 comprised a hygromycin B resistance cassette, comprisingsequence encoding the hygromycin B phosphotransferase gene product(hpt), operably-linked to the Mortierella alpina histone H4.1 genepromoter (GenBank Accession No. AJ249812) upstream of the hptprotein-coding region and operably linked to the Aspergillus nidulansN-(5′-phophoribosyl)anthranilate isomerase (trpC) gene 3′UTR/terminatordownstream of the hpt protein-coding region. Prior to transformationwith pD4, Mortierella alpina were unable to propagate on mediumcomprising 300 ug/ml hygromycin. Upon transformation with pD4,transformed Mortierella alpina were obtained that were propagated onmedium comprising 300 ug/ml hygromycin, thereby establishing thehygromycin B antibiotic resistance cassette as a selectable marker foruse in Mortierella alpina. Evaluation of the genomic DNA of the stabletransformants was performed by Southern. Mackenzie reported thatselection and maintenance of the transformed Mortierella alpina wasperformed on PDA (potato dextrose agar) medium comprising hygromycin.Liquid culturing of transformed Mortierella alpina by Mackenzie wasperformed in PDA medium or in S2GYE medium (comprising 5% glucose, 0.5%yeast extract, 0.18% NH₄SO₄, 0.02% MgSO₄-7H₂O, 0.0001% FeCl₃-6H₂O, 0.1%,trace elements, 10 mM K₂HPO₄—NaH₂PO₄), with hygromycin. Other media andtechniques used for culturing Mortierella alpina have been reported andother plasmids, promoters, 3′ UTRs, and selectable markers for use inMortierella alpina have been reported (for example see Ando et al.,Applied and Environmental Biology, Vol. 75:17 (2009) pp. 5529-35 and Luet al., Applied Biochemistry and Biotechnology, Vol. 164:7 (2001), pp.979-90). Mackenzie reported that the transformation vector pD4 and theMortierella alpina histone H4.1 promoter and A. nidulans trpC gene 3′UTR/terminator are suitable to enable heterologous gene expression inMortierella alpina. In addition, Mackenzie reported that the hygromycinresistance cassette encoded on pD4 was suitable for use as a selectablemarker in Mortierella alpina.

In an embodiment of the present invention, vector pD4, comprising thenucleotide sequence encoding the hpt gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Mortierella alpina to reflect thecodon bias inherent in nuclear genes of Mortierella alpina in accordancewith Tables 69A-D. For each lipid biosynthesis pathway protein of Table70, the codon-optimized gene sequence can individually be operablylinked to the Mortierella alpina histone H4.1 gene promoter upstream ofthe protein-coding sequence and operably linked to the A. nidulans trpC3′UTR/terminator at the 3′ region, or downstream, of the protein-codingsequence. The transformation construct may additionally comprisehomology regions to the Mortierella alpina genome for targeted genomicintegration of the transformation vector. Homology regions may beselected to disrupt one or more genomic sites of endogenous lipidbiosynthesis pathway genes. One skilled in the art can identify suchhomology regions within the sequence of the Mortierella alpina genome(referenced in the publication by Wang et al., PLOS One, Vol. 6:12(2011)). Stable transformation of Mortierella alpina with thetransformation vector is achieved through well-known transformationtechniques including protoplast transformation or other known methods.Activity of the hpt gene product can be used as a marker to select forMortierella alpina transformed with the transformation vector on, butnot limited to, PDA medium comprising hygromycin. Growth media suitablefor Mortierella alpina lipid production include, but are not limited to,S2GYE medium, and those culture media described by Lu et al. and Ando etal. Evaluation of fatty acid profiles of Mortierella alpina lipids canbe assessed through standard lipid extraction and analytical methodsdescribed herein.

Example 44: Engineering Rhodococcus opacus PD630

Expression of recombinant genes in accordance with the present inventionin Rhodococcus opacus PD630 can be accomplished by modifying the methodsand vectors taught by Kalscheuer et al. as discussed herein. Briefly,Kalscheuer et al., Applied and Environmental Microbiology, Vol. 52(1999), pp. 508-515, reported the stable transformation of Rhodococcusopacus with plasmid DNA. Using the transformation method ofelectroporation, Kalscheuer introduced the plasmid pNC9501 intoRhodococcus opacus PD630. Plasmid pNC9501 comprised a thiostreptonresistance (thior) cassette, comprising the full nucleotide sequence ofthe Streptomyces azureus 23S rRNA A1067 methyltransferase gene,including the gene's promoter and 3′ terminator sequence. Prior totransformation with pNC9501, Rhodococcus opacus was unable to propagateon medium comprising 1 mg/ml thiostrepton. Upon transformation ofRhodococcus opacus PD630 with pNC9501, transformants were obtained thatpropagated on culture medium comprising 1 mg/ml thiostrepton, therebyestablishing the use of the thiostrepton resistance cassette as aselectable marker in Rhodococcus opacus PD630. A second plasmiddescribed by Kalscheuer, pAK68, comprised the resistance thio^(r)cassette as well as the gene sequences of the Ralstonia eutrophabeta-ketothiolase (phaB), acetoacetyl-CoA reductase (phaA), andpoly3-hydroxyalkanoic acid synthase (phaC) genes forpolyhydroxyalkanoate biosynthesis, driven by the lacZ promoter. UponpAK68 transformation of a Rhodococcus opacus PD630 strain deficient inpolyhydroxyalkanoate biosynthesis, transformed Rhodococcus opacus PD630were obtained that produced higher amounts of polyhydroxyalkanoates thanthe untransformed strain. Detectable activity of the introducedRalstonia eutropha phaB, phaA, and phaC enzymes indicted that theregulatory elements encoded on the pAK68 plasmid were suitable forheterologous gene expression in Rhodococcus opacus PD630. Kalscheuerreported that selection and maintenance of the transformed Rhodococcusopacus PD630 was performed on standard Luria Broth (LB) medium, nutrientbroth (NB), or mineral salts medium (MSM) comprising thiostrepton. Othermedia and techniques used for culturing Rhodococcus opacus PD630 havebeen described (for example see Kurosawa et al., Journal ofBiotechnology, Vol. 147:3-4 (2010), pp. 212-218 and Alverez et al.,Applied Microbial and Biotechnology, Vol. 54:2 (2000), pp. 218-223).Kalscheuer reported that the transformation vectors pNC9501 and pAK68,the promoters of the Streptomyces azureus 23 S rRNA A1067methyltransferase gene and lacZ gene are suitable to enable heterologousgene expression in Rhodococcus opacus PD630. In addition, Kalscheuerreported that the thio^(r) cassette encoded on pNC9501 and pAK68 wassuitable for use as a selectable marker in Rhodococcus opacus PD630.

In an embodiment of the present invention, vector pNC9501, comprisingthe nucleotide sequence encoding the thio^(r) gene product for use as aselectable marker, is constructed and modified to further comprise alipid biosynthesis pathway expression cassette sequence, therebycreating a transformation vector. The lipid biosynthesis pathwayexpression cassette encodes one or more lipid biosynthesis pathwayproteins selected from Table 70, each protein-coding sequencecodon-optimized for expression in Rhodococcus opacus PD630 to reflectthe codon bias inherent in nuclear genes of Rhodococcus opacus inaccordance with Tables 69A-D. For each lipid biosynthesis pathwayprotein of Table 70, the codon-optimized gene sequence can individuallybe operably linked to the lacZ gene promoter upstream of theprotein-coding sequence. The transformation construct may additionallycomprise homology regions to the Rhodococcus opacus PD630 genome fortargeted genomic integration of the transformation vector. Homologyregions may be selected to disrupt one or more genomic sites ofendogenous lipid biosynthesis pathway genes. One skilled in the art canidentify such homology regions within the sequence of the Rhodococcusopacus PD630 genome (referenced in the publication by Holder et al.,PLOS Genetics, Vol. 7:9 (2011). Transformation of Rhodococcus opacusPD630 with the transformation vector is achieved through well-knowntransformation techniques including electoporation or other knownmethods. Activity of the Streptomyces azureus 23 S rRNA A1067methyltransferase gene product can be used as a marker to select forRhodococcus opacus PD630 transformed with the transformation vector on,but not limited to, LB medium comprising thiostrepton. Growth mediasuitable Rhodococcus opacus PD630 lipid production include, but are notlimited to those culture media discussed by Kurosawa et al. and Alvarezet al. Evaluation of fatty acid profiles of Rhodococcus opacus PD630lipids can be assessed through standard lipid extraction and analyticalmethods described herein.

All references cited herein, including patents, patent applications, andpublications, including Genbank Accession numbers, are herebyincorporated by reference in their entireties, whether previouslyspecifically incorporated or not. The publications mentioned herein arecited for the purpose of describing and disclosing reagents,methodologies and concepts that may be used in connection with thepresent invention. Nothing herein is to be construed as an admissionthat these references are prior art in relation to the inventionsdescribed herein. In particular, the following patent applications arehereby incorporated by reference in their entireties for all purposes:PCT Application No. PCT/US2008/065563, filed Jun. 2, 2008, entitled“Production of Oil in Microorganisms”, PCT Application No.PCT/US2010/31108, filed Apr. 14, 2010, entitled “Methods of MicrobialOil Extraction and Separation”, and PCT Application No.PCT/US2009/066142, filed Nov. 30, 2009, entitled “Production of TailoredOils in Heterotrophic Microorganisms”.

1.-114. (canceled)
 115. A method of producing a triglyceride oil, themethod comprising: a. cultivating a recombinant oleaginous microbe, themicrobe comprising an exogenous gene that encode a β-ketoacyl synthaseII (KASII) peptide; b. recovering the triglyceride oil from saidrecombinant oleaginous microbe; and wherein the triglyceride oil isenriched in C18 fatty acids or reduced in C16 fatty acids.
 116. Themethod of claim 115, wherein the triglyceride oil is enriched in C18:0and C18:1 fatty acids.
 117. The method of claim 115, wherein thetriglyceride is reduced in C16:0 fatty acids.
 118. The method of claim115, wherein the triglyceride oil comprises at least 60% C18:1.
 119. Themethod of claim 115, wherein the recombinant oleaginous microbe ismicroalgae.
 120. The method of claim 119, wherein the microalgae is thegenus Prototheca or Chlorella.
 121. The method of claim 120, wherein themicroalgae is Prototheca moriformis.
 122. The method of claim 119,wherein the exogenous nucleic acids are codon-optimized for expressionin microalgae.
 123. The method of claim 122, wherein the codon optimizednucleic acids contains the most or second most preferred codon of Table2 for at least 60% of the codons of the coding sequence.
 124. The methodof claim 115, wherein the recombinant oleaginous microbe comprises asecond exogenous gene, wherein the second exogenous encodes a sucroseinvertase.
 125. A triglyceride oil produced by the method of claim 115.126. A recombinant oleaginous microbial cell, the recombinant microbialcell comprising an exogenous gene that encodes a β-ketoacyl synthase II(KASII) peptide, wherein fatty acids of triglyceride oil produced by therecombinant microbial cell is enriched in C18 fatty acids or reduced inC16 fatty acids.
 127. The recombinant oleaginous microbial cell of claim126, wherein the triglyceride oil is enriched in C18:0 and C18:1 fattyacids.
 128. The recombinant oleaginous microbial cell of claim 127,wherein the triglyceride oil comprises at least 60% C18:1.
 129. Therecombinant oleaginous microbial cell of claim 126, wherein therecombinant oleaginous microbe is microalgae.
 130. The recombinantoleaginous microbial cell of claim 129, wherein the microalgae is thegenus Prototheca or Chlorella.
 131. The recombinant oleaginous microbialcell of claim 130, wherein the microalgae is Prototheca moriformis.